Hello and welcome to BW forums
Don't worry about your LO being sleepy now, he will soon "wake up"!! I'd enjoy the Y time while you have the chance
If you want to put a little A between E and S and nappy change is enough. If LO is really asleep I'd probably just put down for the nap and tell him, reasonably loudly, "I'm putting you in your bed so you can have a lovely sleep, call if you need me". He doesn't understand the words right now but he will in time and he will still know you are telling him something reassuring. Tracy said to communicate with our LOs about what we are doing when we are going to pick them up and put them down so it's just that, letting him know what's going on.
Unless there is a weight gain issue and you really have to feed on the clock I'd just let him nap until he is ready to wake, not more than 3hr straight but no need to wake him after 1.5hrs, hope that makes sense. The routine will gradually form and as he gets a bit older you'll see him awake longer.
Honestly if he is napping well now go and get yourself a shower and a cup of tea, or a nap