Head To Head OT

I wass in the 6th overtime, my opponent didn't score a 2pt conversion then on my drive I threw a pick. My next drive started the 7th OT, and I threw a TD for my 2pt conversion and took the lead 17-15. On my opponents next drive I got a pick 6 which gave me a 4 point lead 19-15 which should have ended the game. Well it made me drive again, this time from the 25 yard line (like the game started over) well I ended up throwing a pick 6 and lost 21-19. Is this common, has anyone else experienced something like this? I have a 3min clip but it's to large to upload, and in order to understand you have to see the full clip.