Lump Lower Abdomen

Unknown

Hi, girls! I noticed a lump in my lower left abdomen. It is down very low, below my pelvic bone, almost where my ovaries would be. It hurts to touch and the area is achy. I am 18 weeks pregnant. When I googled it, the only thing that somewhat makes sense is ovarian cyst, but I have no clue. Any ideas to what it could possibly be? Thanks!