Here's the best idea:

Go see a doctor. Strained will turn into torn more than likely, regardless of what every internet Ph. D. here wants to tell you.

The value of the advice here is equivalent to what you paid for it: zero. It is either really basic or experiencial and may not apply to the level of injury you may have.

It's a knee, you need them for walking and most importantly riding. I would not mess around with ice packs or armchair voodoo. Get it looked at.