What Causes Constant Knee Pains?

I developed Knee pain on my right Knee 3 weeks after a low-risk sexual activity with another man. Is this related to ARS symptoms or not related at all? I did go hiking with some friends and I thought this could possibly be from that but the knee pain didn't start until 1 week after my hiking trip.
The knee is worst after waking up then it gets better through out the day but is still present. I'm 25 years old male.
The knee pain has been on and off for two weeks.