If you've taken 9 home pregnancy tests and 2 tests at a clinic since your last period on April 22 and they've all been "positive", then you're certainly pregnant. The test in a clinic showed "positive", so believe it! You wouldn't have had 10 "positive" pregnancy tests and you wouldn't have gotten 10 "false positives". Your last period began on April 22, and so you're now around 4 to 6 weeks pregnant.
Just so you'll know: Back pain and sore boobs are NOT usually symptoms of early pregnancy. Back pain CAN be a symptom of a urinary tract infection, but sore boobs are not. If you have a UTI, it will "burn" when you pee.You can have a UTI and be pregnant; but a UTI doesn't mean you're pregnant. Pregnancy tests aren't looking for the bacterial infection from a UTI - they're looking for the "pregnancy hormone".
You don't "feel" pregnant? What are you supposed to "feel"? In early pregnancy, what makes you think you're going to "feel" any differently than you always do?