I have one credit card with a $500 limit that I use only for small things, and I pay it in full each month to avoid interest charges. I've also arranged to give it (along with my bank card) to my son if I become hypo/manic. It's taken me years to build enough credit to have a credit card in the first place, and it's only been recently that I trust myself enough to handle it responsibly.

It sounds like you've still got doubts and you may be better served by keeping the card with your mom and only using it in case of emergencies. Especially if you've got a pattern of manic behaviors at certain times of the year like I do. Of course, you're the only one who can decide whether having a card is too risky. I wish you the very best of luck.