Intense arm pain?

Im about 5 weeks. Yesterday I got intense arm pain radiating up to my elbow through the night to this morning. I think I’ve had tendonitis in this arm for a while now, but the pain starting from yesterday is a lot more intense to the point where I can’t really move my arm.  I haven’t really been doing anything different from normal, and actually have been trying to lift less things. Does anybody else have this problem or know anything about this?