I am a 50 yr old female. Last evening I began to experience intense lower pelvic pain. It made me feel faint and nauseous. I put my self on the bed and can only describe the pain like a uterine contraction, very intense. It took possibly 10 mins to pass. The remaining evening was without problem. Next day I can still feel now that my uterus has been in contraction with awareness drawn to it, feels heavy. Absolutely no possibility of pregnancy. Do I need to follow up on this as a concern?