My python missed, what should I do?

I feed frozen thawed to my three month old ball python. I have never had a problem feeding in the past. This time, he struck once and missed, struck again and grabbed the tail end, let go, and then struck again and grabbed the head. He is now in the process of swallowing it. He looks a little different than he normally dos when swallowing. I can see the lump more than I usually can, but the mouse was the same size as I usually feed. Is this something I should be worried about? Is there something I can do so that he doesn't do this next time? I don't want to stress him from feeding.