To think my manager should be more understanding?

I got a call from my 3 year olds nursery to pick him up as he had been sick and he didn’t look right/looked pale. Now when my child is ill, I go into full on panic mode because he’s my baby and of course i am going to worry about him! As my phone rang loudly in front of my boss. I didn’t realise it was on loud and apparently were not allowed our phones on us. I apologised and said i will give his nursery the work number so they can call that in future but I have to go and collect him now and I will make it up to you when I am back. Don’t get me wrong, she’s absolutely lovely and I can sort of understand why she’s pissed off.

She then said well what have you got left to do? Can’t you just go and finish them off as they need to be done first. A colleague of mine was about to leave and she said she also has to go so that left just me. She then said why was I taking so long doing things and why have I still got loads left to do. I so things properly and thoroughly, that’s why I take my time instead of having spare time at the end and haven’t done the job correctly. I’ve done extra time for them, I have stayed on whenever they’ve asked me to. I started a month ago after leaving my other job (worked there for 6 years)

I have not been unreliable and I am always there on time and I do my job well. Now I am just riddled with guilty and worry :(