Hello Sarah
I know you said you don't think it's teething, but from the way your lo is refusing all 3 solids, it could well be teething. I wouldn't reduce the amount of milk he is having as his milk intake is the most important until 12 months. I would try to put teething gel 15 mins before solids and see if it makes any difference.
As for the activity in the cot, that is highly developmental, and I would normally advise to increase a times slightly. Except you lo is OT at the moment, so you need to decrease them first in order to remove OT, and then start increasing them again.
With the feeding to sleep you are entering a dangerous path. You have done a wonderful job with sleep training, and your lo is doing great at independent sleeping. I wouldn't get him used to feeding to sleep. You do it a couple of times and he'll come to expect it. Unless you know he is hungry of course. But that didn't seem to be his need since he didn't settle after feeding.
So here's what I suggest;
-Keep milk feeds same (both sides)
-Teething gel 15 mins before solids
-Reduce a times by 15 mins for 2 or 3 days or until necessary, and then start increasing them again to 15 mins more than he was normally doing.
-Do not feed to sleep if possible
-Use shussh/pat or PU/PD to extend naps in order to avoid OT. Hopefully with the routine tweak you will not need to extend for long.
Let us know how it goes.
xxx
charm