Welcome here on hcm.
For you I will suggest that you must consult your family doctor so that an expert examination will rule out any abnormality which will go unnoticed.
For pain you can try Nimsulide 200mgm s.o.s...
You can also use contraceptive
pill for this purpose.
Pain during menses is suggestive of ovulatory menses and use of contraceptive will make it non ovulatory and so the pain will go.
This type of pain also vanishes in some cases after pregnancy