Here are some doozies that I struggle with pretty much daily:

* I feel exhausted, but when I take a nap (or go to bed for the night) and get some solid rest and wake up refreshed, I feel guilty and frustrated because I think I wasted time that could have been better spent elsewhere.
* I get excited about purchasing some of my favorite hobby material (a game on Steam, for example, or an RPG sourcebook), but then I lose interest almost immediately.
* I feel guilty spending money on anything that isn't strictly "essential," and that guilt ends up making it hard for me to enjoy it - even when there are literally no other negative factors.