Hmm your lo is still very young I would try not to stress too much about keeping him awake during the day. How often do you feed? Falling asleep on the bottle is a sign of tiredness, ideally they should have just woken from a nap at this time so shouldn't be tired. Easier said than done though! You want to disassociate feeding from going to sleep if you can. I had to stop feeding at this sort of age once my los eyes started to droop and give him bottle back once his eyes sprung open.