Sorry you and babe are going through this.
You mention that he only fall back asleep with you - that could be your problem.
When babies/toddlers wake up crying or screaming, if it's not from a health problem (ear infection, teething, acid reflux, etc.) it's usually because they have fallen asleep with a prop (bottle, soother, mom's arms, etc.).
So just thought I'd mention that - is he able to go to sleep on his own at all? You mention bottles before bed - so if he isn't able to go down on his own entirely without you or milk, that could be why when he wakes at night (all babies do), he doesn't know how to go back to sleep on his own.
I had one like that. Also had tubes etc. Sometimes babies who wake from ear infections get into a pattern of waking, and of course we soothed them when they were sick. So they become dependent on mom and dad coming in to soothe them.
I would suggest from my own experience making sure he gets enough sleep during day (whatever he needs to nap at this point) and I would not push his bedtime back. Babies need sleep and become worse at sleeping when they don't get enough. They become out of sorts (just like we do).
I had a bubble aquarium on the side of my crib that helped my firstborn over needing me to fall back asleep. He would press it himself and it would soothe him back into sleep. It was a prop, but at least he could do it himself and didn't wake us up. But try to get him to fall asleep on his own if he isn't already.
There is separation anxiety around that age - if that's the case then you have to do some sleep training - go in and just shoosh, make sure he's ok, and leave once he settles.
If you've already done that - I would set up an appointment to just have him checked out.
Good luck :)