I've had both ACL ligaments torn. Repaired the left one, didn't do the right one. I wear a Donjoy ski ACL brace on the right. I can ride, but it does get swollen in both knees after a long day.
You've got one of two choices. Go ride, find out you DID tear/sprain some ligaments that way(BTW, doesn't matter if you take it easy in snowboarding, if you did some damage, you are going to find out if you ride).
Go see a doctor, get a lachman test done or MRI, and go from there. Asking for medical advice here isn't in your best interest.
Having said that, if you did a jump-stop and hurt it that way, that is basically what your ACL handles. The forward and backward motion of your knee out of joint. The MCL and PCL handle lateral more or less.
Me? I would opt for seeing a doctor first. It'll snow again, but your ligaments won't regenerate.