Okay my boyfriend and I we had anal last week but today is Thursday and I'm feeling like my belly it's really getting hard I'm pregnant or noo?

Too soon. I week is too soon for you to notice changes in your belly even if you did conceive. You are obviously extremely concerned. Start a reliable method of contraception now so that you don't have to go through so much anxiety in the future. Pregnancy from anal intercourse is unlikely but not impossible if sperm got on the vulva. Hope this helps.
Not yet. Even if your boyfriend mis-aimed and you actually had vaginal sex, it takes several months for the signs of ordinary pregnancy to show. At one week that is not possible ( have you had unprotected vaginal sex weeks or months ago?) Given your concern about pregnancy, next time a condom should be part of your sexual routine.