I've partially torn my ACL ages and ages ago (school years). Studs got stuck in the ground as I was tackled. Knee went with the momentum of the tackle as my foot was stuck.
It's fucking horrible.
I was taken to A&E for x-rays and I think you should definitely get it checked out. It's something you'd want diagnosed and treated correctly so as not to cause further issues in the future. Was on crutches for about a week and rested it for a few months, no sport or anything. Didn't have physio or anything but did exercises at home when it felt better.
In fact just thinking about when it happened it's making me queasy.