Hello,
These symptoms are due to premenstrual symptoms and having sex before periods is not going to help. You can control it by lifestyle adjustment. Drink plenty of fluids, eat frequent small meals, fresh fruits and vegetables, cut down on caffeine and eat Calcium rich foods include dairy products, dark green vegetables, nuts, grains, beans and canned salmon and sardines (with bones). Calcium supplements may also be used.
You can take OTC pain killers for the muscle cramps.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
I have sex on my period because it helps with the cramping. So, yes, it can at least help with the cramping.