Well, not deciding what binder to buy is, I guess, procrastination, maybe due to low self esteem of inexperience with the item to be purchased. Whatever the reason many people have procrastination which is a minor problem in the scheme of things but can be an annoying one is progress to be more decisive isnt made.
Worrying about people views of you is also low self esteem and placing peoples thoughts so high is a problem because you will always get other people thinking negatively of us and talking about us behind their back- its human nature. That also becomes a problem if it is extreme, otherwise when someone at a gathering says "gee Tony, were your ears burning the other day?" meaning people were talking ill of me, I say "do tell me, if I dont know what is being said it cant hurt me".
Dwelling on topics is another matter. I came from a dwelling family, my mother would talk for hours and hours on the same topic and repeat herself endlessly. What ever her illness she was in denial so we never officially found out but I have my suspicions and I'll leave it there, but it is an issue because in social circle people get turned off as they like to have fun, not talk about problems.
You binder selection issue wasnt really dwelling, it was indecision. Dwelling is thinking over and over about a problem and making no real progress in terms of fixing the problem and moving on from thinking about it. It can be anxiety related.
If I can suggest- you dont mention your age but I think if you are in maturing age, teens maybe some of these issues are to be expected. We all like to be accepted as who we are but if not at full maturity doing silly things etc is like waving a flag to your friends that attracts attention. But on the other side of things you should be yourself right? - mmm, being yourself is great in theory but horrible in practice if you are even slightly different than the run of the mill teenager. So there is a fine line between being yourself and being a little reserved so you dont attract attention. And a tip- people like to talk about themselves so in social circles always ask friend questions, you'll be liked more and learn more about them.
In summary if this situation worsens see a GP
Beyondblue topic worry worry worry