What Causes Bruising Feeling In The Abdomen And Pain During Sex After Coming Off From Contraceptive Pills?

Hi, for the last couple of months since I went off the pill I have been getting a dull bruising feeling in my lower abdomen area, sometimes more to one side & it also feels like it s towards the back near my bottom in the bowel area as well. During sex with my husband, it feels like I ve shrunk inside, no unusual pain in outer vagina, but more on the inside cervix & vaginal walls area. During sex is when I feel a more sharper bruised feeling, which can sometimes be a bit unbearable, but not always, depending on the position. I don t have bad period pain or anything when I have my period, just the normal. My bowel movements are normal, it s just this bruising feeling, which is more obvious during sex but not always overly painful. What could this be?????