And if so, how long did it take to recover, and how bad did it hurt? Did it happen a second time?
I think i did it. Hurt like heck for about 5 minutes then it gradually subsided. I can walk and turn and squat just like it never happened. The only thing thats worrisome is that when i was crawling around under my truck tonight, i bend my leg in a wierd position and there was a slight sensation that it was about to happen again, this time with no pain.

Looking for firsthand experience here

Yep.
Mine started doing it wrestling in high school and still does it from time to time. The worst is when it pops out driving and you literally have to fall out of the truck to get it back cause you just can't straiten it up sitting in the truck. Don't let this scare ya to much as you can take care of it for a while and it should get better, I did not and it just got worse.
My daughter dislocated hers last summer swinging at a softball. It was good up until wrestling season when it came out again. I made her where a brace or tape it for the rest of season and it seems to be healed for the most part, but she is still careful with it due to my experience.

If you are doing lots of physical work and straining it KT tape works great to hold it in place. There are videos on proper placement of the tape. A knee brace with the hole over the cap will also help tremendously for day to day activity to hold it in place.

You most definitely want to address letting it heal and not be stubborn like me and pay for it the rest of your life. A few weeks of being careful is worth the hassle.

10/22 - how old are you? This is something that usually affects younger folks, particularly teenagers, and especially teenage girls. Younger folks are still developing and certain leg muscles develop quicker than others, putting a sideways pull on the knee, making it more susceptible to dislocation. (recent activity/exercise can also cause one or more muscles to become over developed) This is very painful but most time the dislocation is reduced with minimal movement with little to no damage. Once you have dislocated your knee it is something that easily repeats itself until fully healed. Your tendons and ligaments have been stretched, and need time to regain their strength, "locking" the knee back into position. Take Andrew's advice and give it time to heal. Different schools of thought recommend heat or ice, so I can't advise you there. If you know anyone with sports medical training or a physical therapist, they should be able to give you sound advise.

I never have, my QB did last season...and he won the Super Bowl!

I am 19 yrs, male. And yes, thats exactly what i did: pushed a heavy object sideways with my inner leg.

I wonder if it will pop with every step i take after it heals

Once it heals, you should be fine with no problems. But you need time for the tendons and ligaments to tighten back up and stabilize the knee. Right now everything has been stretched out and is loose. A brace or ace bandage MIGHT help, but you should get someone's opinion on this with some medical/sports injury experience.

Take the advice given and take care of it and get it looked at while you’re young. I separated my shoulder when I was 15 in baseball, never really did anything about it and ended up separating it 8-10 more times over the years from sports, trapping, rope swings, jumping off bridges into water, slippy slides, etc...It’s been 17 years now and now I can’t hardly play catch with my 4 yr old kid.

Once on my right knee and 4 times on the left. Baseball 7th grade first time. Knee cap would end up on the side of my leg each time. The others were from playing basketball and simply just walking on ice one time. The first couple times I ended up in a complete leg brace, the others popped right back in and just took it easy for awhile after. The doctors figured the groove your knee cap fits in was too shallow in both my legs, which is why it would pop out so easy. Been 15 years or so since the last time, but all winter walking on ice it’s in the back on my mind. I’m 38 years old and still play/ref basketball and everything outdoors without any pain yet, lol. Hope everything goes good for you.

There is a special brace to keep the patella aligned while bending the knee. There are strengthening exercises that will keep the patella in alignment. Any physical therapist can show them to you., probably on youtube as well.

Just seeing that title made my eyes water!

When I was in my early teens I trapped a nerve in my knee. I'll never forget how, as I rolled around, clutching my knee and screaming my lungs out; The PE teacher ~ who happened to be near by ~ saying, perfectly 'normally', " He's trapped a nerve. " And someone else calmly responding, " Yep. That's a trapped nerve. "

Don't even want to Think about a dislocation! Gnarly!

I saw when Victor Oladipo from the Pacers had it happen, took like a year for him to get back on the court, it was nasty.
I'm assuming there are different levels of severity of injuries so who knows, good luck