I said that this was the time I'd watch her kid.
Did you have an agreement to watch each other kids?
Yes, I've been so busy lately and now I have time to do my part.
It's good that you're babysitting your friend's kid. It's ok if you're unable to do so anymore.
This doesn't mean I'm not a nice person or that I don't care.
Of course not. Sometimes we just don't have the time. The most important thing is that you are willing to work on the agreement.