7:45 awake8:05 eat8:20 awake9:00 sleep9:45 awake
Here, he was awake for 1:15 and then you got a 45min undertired nap.
9:45 awake10:50 feed11:15 sleep11:45 awake
Here, he was awake for 1:30 after a short nap then you got a 30min overtired nap.
11:45 awake12:35 sleep1:50 awake
Here he was awake for 50min after two short naps and he napped 1:15. This tells us two things - he needs to reduce his A time a little bit after a short nap and he *can* sleep longer than 45min, so he can make it through from one sleep cycle to another.
5:40 sleep6:20 eat - head upstairs for the night6:30 awake7:00 eat - extremely fussy until asleep8:30 sleep - rocked until very asleep
Here, he had a 40min nap and woke at 6:20 - cannot be expected to sleep again 40min later at 7am, so here, you're rocking him while he's not tired (hence he's fussy, saying mum! I don't want to sleep yet) then he got overtired and struggled to get to sleep.
8:30 sleep - rocked until very asleep1:20 eat
This is a good long stretch
6:45 wake & eat7:05 awake8:15 sleep - woke around 8:45 and rocked back to sleep all in car seat10:05 eat10:20 awake11:50 sleep12:45 awake1:00 eat1:10 awake2:25 sleep3:15 awake
So the first nap - its pretty normal to get a 30min waking that you can resettle at this age. I think if you stick with 1.5hr for the first A time, he will soon sleep fine for that nap by the looks of it. The second and third naps look to have been undertired naps after 1:45 and 1:40 respectively - How was he when he woke from those naps? Did you attempt resettling? Do you have white noise that turns off after 45min?
I think you just need to focus on getting your A times right and do shush/pat and slowly reduce the assistance you're giving him to fall asleep.