Not pregnat related it.

So i have some pain on my left elbow it almost feels like if it was a bruce. But i dont have anything on my skin no brusing nothing at all. Theres times that it hurts and times that dont. But the pain is from inside not outside which is weird never had that before. The pain is nothing big very small but its just something that bothers me here and there. Anybody have an idea of what it can be?