I really remember this feeling and I hope I can help - don't know if it will, but this is the basics routine we used with my son at this age:
up in the morning by 7am
First bottle / feed straight away
Then quick change, wash, and dress, and some kickabout time on his playmat using his baby gym thing, and general playtime/social time with me
9am upstairs for his nap, usually three quarters of an hour or an hour.
10am up and playtime again
11am next feed
12 noon Upstairs for nap till 2.30ish
2.30 playtime
3pm next feed then kickabout time
4pm up for very short nap, no more than half an hour
6pm took all clothes off to let his bum get some air! kickabout on his changing mat, then bath, dress for bed, last feed, and bed by 7pm.
I have to stress that this was what we aimed for; at 11 weeks we definitely had days when he went 'off message'! Usually this was with the feeds as he was hungry and grizzled for his feeds earlier than 4 hourly. The thing was if he had them early he took less and this led to a cycle of snacking, which meant he slept for less time, which meant he got tired and grumpy - this is why we wanted a routine for him because the moment we tried it we saw how much happier he was.
Obviously all babies are different but using this routine my son became such a happy little baby and was a complete joy.
There were days when he did odd things like fall asleep during his playmat time but this was rare. The routine seemed to 'fit' him perfectly physiologically for the most part.
I found my health visitor completely useless, couldn't recommend a routine, but then as weeks wore on and I took such a content baby to clinic for his weigh ins, she'd say 'oh, he's so happy because you're doing everything right!" Cheers, no thanks to you, I thought!!! Have you tried the Gina Ford contented baby book - that's where my routine was lifted from.
The 4pm nap was the one my son dropped first by the way so don't know if your son would go for this at 11 weeks.
Hope some of this helps. I had a friend who couldn't use it because her son was just so sleepy, kept falling asleep all day but she kept plugging away and a few months on he took to more of a routine. Good luck, whatever you decide to do!