That is just way to clean of a cut, I think. No signs of stress...and shouldn't the metal look even a "bit" twisted. No way...someone's messing with you...looks like they literally want to see you get hurt.
Not sure how much the bike is worth, but if you truly think the metal just fatigued, I'd scrap it and start over. Can you imagine catastrophic frame failure at 20mph???
Hope you're at least wearing a helmet.
Don't mean to sound like "Gloom and Doom" but man, that aint funny, and you can get hurt or killed. Be safe, man.