Worse meltdown yet

I miss my daughter as I used to recognize her, she is such hard work. Had the worse meltdown this morning, more than an hour and a half of screaming crying etc. Started with one thing ( wanting to get craft bits out, I said after we got dressed) to something else.( Not being able to eat two pieces of fruit at a time) - she'll take a bite or two then leave the rest... Everytime she started to calm down, something else kicked it off again. Had babys first jabs today and she was happy after but usually screams in the car - had them both screaming all the way home. I would really like to opt out of the rest of the day. The oldest behaviour is just such hard work and has got worse since baby, understandably a big change. But I barely recognise her. I make such a point of having one on one fun time with her but she usually ruins it with tantrums or major boundary testing - will literally go on a rampage of all the bad behaviour she can think of. Just a vent. Feeling so drained and I hope this passes soon.