Had sex 3 weeks after leep and now im bleeding and cramping im in menopause is this dangerous I been bleeding and cramping for 4 days?

Likely not. Cervix is likely not completely healed and the uterus still reacting to the inflammation at the cervical level. If pain or bleeding persists, you should check with your surgeon or if you have any questions at this point.
Call doctor. Don't panic (please) but if bleeding persists call your doctor (the one who did the leep) promptly - like tomorrow mornign.