Working full time with a difficult 13m old? Going crazy

[Lemonmiracle]

So I recently got a new job (maternity from the old job finished and I went straight here). It's a great job and great pay but very very tough and I'm working full time. Have asked about part time but due to the nature of the job they need me to be full time for the training period (6months). I'm basically a walking zombie. I'm drained 24/7. DD has changed so much since I started, it's been around 2 months so far and the hardest 2 months of my life.
My mum watches her whilst I'm at work and she's fine but as soon as I'm back she starts playing up, screeching smacking etc. She also gives me a negative reaction when I come home but will run to daddy fir cuddles when we both go to collect her from mums. Night times are mental, she barely sleeps, suddenly loads of wake ups and loads of screeching to get her way. She's slapped me across the face countless times. I'm so so tired, on my morning commute sometimes I want to cry lol.
I feel so guilty for leaving her but even more guilty that when I come back I just feel irritated at her behaviour. Just wanted some words of comfort I guess from a fellow mum

Bump?

Its really tough.

I went back after 11 months, full time (5 days a week commuting etc) - its intense suddenly having to be back into work environment, communicate and work alongside adults, then go home and be a mum, have shit sleep etc etc. You cant "switch off" for a second! I felt absolutely zapped for the first few months but it DID GET BETTER, once I readjusted and it wasn't so much of a shock to the system.
DH did a lot of the bedtime stuff and night wakes when I first went back, to accommodate for the huge adjustment and exhaustion I was feeling - can your partner do the same? Working mothers are supposed to work as if they don't have children, and child rear as if they don't work. Its a lot.
I would also definitely negotiate flexible working after your training period if its an option. Hang on in there OP - youre doing great.

@nomchonge1 thank you so much for the words of encouragement and I feel much better knowing I'm not alone in feeling this way. I kind of feel like a failure as a working woman and a mother. DH has tried but she will not settle with him, it's me she wants but also feels like she's angry at me for leaving or something.

Hoping I can battle out 4 more months and go part time!

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