This is my 4 week of taking 125mg and I have noticed headaches bu...

This is my 4 week of taking 125mg and I have noticed headaches but not sure if this is a side effect. I have headaches all the time the only thing is sometimes it seems like they come on when I first take my dose. But later in the day everything seems fine. Started having knee pain in one of my knees that I injured about 8 years ago not sure if this is a side effect as well, but I will be tracking it and I will be calling my doctor first thing on Monday. I have alot of allergies to medications so hopefully if this is all do to the medication, I can take one of the other that has been mentioned.