I Wasn't Ready Yet...

This is weird but I'm not sure if anyone would understand. My best friend got a new puppy last week, and it was so cute and fluffy at first... But as the days went on, I realized taking care of her was harder than she thought. She kept forgetting to feed the puppy or clean up after them properly. So one day when they asked me for help, I felt bad but just told her I needed time alone instead because I wasn't ready to be responsible like that... And now I feel a bit sad seeing how much work it is and wondering if I made a mistake by not stepping in more.