Congratulations, time traveler! You've managed to get yourself stuck in a predestined loop of paradoxes. Don't worry, it happens to the best of us.
It's because you tried to change the past, duh. You see, time is like a big ball of twine, and you just went and pulled the wrong string. Now you're stuck in a never-ending cycle of "what ifs" and "but ifs".
Good luck, and may the odds be ever in your favor!