Hi. I Have A Knot In My Upper Right Buttocks

Hi. I have a knot in my upper right buttocks area from having shots when sick. I found this knot over 2 years ago. It is quite large but has never really bothered me. Now I have knots coming up in my hip on the same side that are painful and sensitive to touch. When I try to feel these they feel as though they may be connected somehow to the one in my buttocks area. I am wondering if this is normal?