My knee hurts when I bend it help?

So my knee hurts when I bend it the pain is on the top left corner if youre looking at your knee. I rested for 4 days and it kinda went away but then I ran today and it came back. I have a 10k race coming up on july 29 and I wanna know how to prevent this. Do you guys think Ibuprofen would help me? i really need help