What causes severe anal cramps?
should check for anal lesions
Thanks for your query.
As you have symptoms of anal cramps, definitely you should get yourself checked for any anal lesions, not necessarily warts or cancer. Since sigmoidoscopy was clear 9 months ago, very little chance that something has developed in rectum so soon.
Anal HPV infection is possible even though cervical HPV is negative, though chances are low. But no need to get HPV checked now from anus unless some visible lesion is there. Undiagnosed HPV infection does not explain your symptom to well. It may be more of a functional problem with the sphincter.
Hope this helps.