mommy guilt

This morning, my one of two mornings during with the week with just Lily I spent organizing paperwork.
Not the best idea, but in the afternoon I get so sleepy and tired, NOT that I am napping, but my motivation is gone and I REALLY needed to get this done, so while Lily played quietly by herself I organized paperwork.
I feel so much better now that things have been organized and I know what bills need to be paid when, but I feel guilty for not hanging out with Lily for an hour this morning.
Which reminds me.
I feel guilty for putting Lily in 3 day a week preschool.
I feel guilty for working.
I feel guilty for not always being fully engaged because I was studying or cleaning or others things that are not really important like email.
Mommy guilt, hate it, but I don't know how to fix things.
I have to work to pay bills and I like it. So then I feel guilty because I like working. I feel guilty that staying at home with her every day is not enough.
I could go on, but then I just might feel worse.
Did my mom or grandmother have mommy guilt or is it just the current societal pressure?