I had the same kind of problems which I mentioned in my log, although I was wearing wraps.
My problem was that I was putting too much wrapping on my palms and the wrap was also too tight on my thumbs. Therefore I wasnt making a tight enough fist which was putting pressure on my wrists when throwing punches. This was only 50% of the problem and the other 50% was just getting used to throwing a lot of hard punches. Give it a few more weeks and I can guarantee your hands and wrists will get used to it.
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