Not a big deal and don't worry too much

Everyone fails sometimes at work. You are not exceptional. I suggest that you just suck it up and move on!!

Why it is not a big deal? - I don't think you will be fired or something like that based on your story. I think you survived, and that's most important...

How to deal with it? - First, don't blame anybody but yourself. Don't blame Boss A, cause he did what he needs to do. Don't blame Boss B, cause the bad communication between you and him is mainly caused by you. Don't blame team B, cause they don't really need to help you if you did not ask for help. Blame yourself for bad communications all throughout.

Second, improve your technical skills as well as, more importantly, communication skills. Report your work plan, progress, issues, suggestions, and results to both A & B. Ask sincerely for help in group B and try to get alone with others.

Third, tell yourself that there is no politics in your work place (even there is in reality). You are not ready yet to play games, so just pretend there is no such game. Your mindset needs to focus on your work and your communication skills, not the relationship between others, especially the two bosses. It's none of your business!!!

Hope this helps a little.