I didn't know i was getting a period until it came and had unprotected sex the whole time a week after my period i'm tasting blood and urinating alot?

Possible pregnancy: It sounds like you were having unprotected sex around your fertile time. However a pregnancy test often isn't positive until you have missed a period. Check the test 2-5 days after the period should have started. You said you are urninating frequently - if you also have pain with urination get checked - you could have a bladder infection.