For about 3 or so days now my knee has been in constant pain and has been locking in place for no reason. Whenever I move it, it pops and sends pain shooting through my leg. What could be the cause of this?
You need to see an orthopedic surgeon for some imaging and an exam. No one on here can diagnose you. I would suggest elevating and icing the knee, use an NSAID for the discomfort (10 days max), don’t stress it with activity and see a doc ASAP.