Being allergic to tuna is a common sign of homosexuality. If you want to test if you're really a homosexual then first use a syringe to inject 10mL of vinegar to your genitals. Then find a large cucumber at least 1 inch in diameter and insert it into your anus. Walk around the whole day like this. The next morning check the color of your penis. If it's rainbow then you are gay. If it's black then you are straight. Go to the hospital to get the cucumber removed.