Thanks guys, reasurring to know it's kinda normal. As you can probably tell he is my first and I am getting myself into a bit of a tizz, trying to get into a routine with his daytime sleep but he doesn't seem keen to be manipulated!!
Today seems to be going a bit better than usual though, he has had 3 45-min naps so far and will probably be needing another one just before 4pm. So if he naps from 4pm - 4.45pm he will be on for a 1845 bedtime which is pretty normal for him.
I think the key fr us is letting him have 2 naps in the morning which he really seems to need, but then keeping him awake a little bit longer in the afternoon (2 hours instead of 90 mins), so then he ends up having his last nap of the day around 4pm. Things seem to go a bit awry when he ends up needing his last nap at 5pm, as he really fights it then (as if he knows it's too near his bedtime!)
My ds is 15 weeks old and is similar. He usually managed about 90 minutes awake time and then his nap can be anywhere from 20 minutes to 2.5 hours. He usually does a 45 min nap in the morning and then if I am lucky a long nap around lunchtime and then sometimes a cat nap at around 4.30. Again it depends if we are out and about in which case he might drop off, or he might stay awake longer if we are just at home.
I stressed about this so much with my daughter but this time around I am kind of going with the flow a bit more as I haven't got the time to devote to trying to sort out a proper routine.
Personally I disagree with your HV. I think ds does shorter naps/wakes after 45 mins when he is over tired.
Also there is alot going on at this age with growth spurts and developmental leaps (see The Wonder Weeks book/app/website). I think once they start crawling and get more tired out they start doing better naps. I think that as long as they are going down easily and sleeping reasonable stretches at night the naps will fall into place. Good luck!
My LO 18weeks has 4 to 5 naps a day totalling between 5 and 6 hours. He's awake time is 1.5hr to 2hr. Has been know to stay awake up to 4 hours but this is rare and we just skipped last map of the day and went to bed an hour early. At home he will be napping from 45mins to sometimes 2.5 hours. We have no routine with naps except he goes down after 2hrs of being awake, nap times vary as we never know how long each nap will last for.
DS (17 weeks) seems incapable of staying awake for longer than 90 minutes unless we are out somewhere and he is being massively stimulated in which case he might make it to 2 hours.
He then naps for 45 mins. So over the course of a day he will typically have 5 naps - is this ridiculous?! It feels like he is getting in and out of the crib all day long when we're at home!
The HV advised I should try to stretch him to stay awake for 2 hours, which could result in him having 4 naps each day instead, but I am not sure if this is a good idea: he generally becomes a shrieking, inconsolable mess when tired during the day :-S