I got to admit, i had a little laugh when i first read the headline =P .. Anyway in no way does anal sex automatically mean آپ are gay. Most straight men find anal sex to be the best actually .. یا so i've read :| lol
NO, there are many positions of sex. Pick up cosmopolitan sometime. If your a guy, and someone looks at آپ weird just say it for a gal pal. In the butt یا from behind is called "doggie style". Woman on bottom guy on سب, سب سے اوپر is "military style" probably the most common.