I've seen blood when i'm wipping after being on toilet. is that possible because of anal sex? do i have hemeroides? it also stings for a week now

Yes, maybe, get help: Blood in stool is a warning sign. Brisk bleeding warrants emergency care. Causes of bleeding may be predictable (e.g rectal trauma), but evaluation is always appropriate. A rule of thumb (but not absolute): black stool means bleeding comes from upper GI tract; grape jelly stool from small bowel; silver stool from biliary tree; burgundy stool from right colon; red blood from left colon to anus.