15 month on 1 nap

[DC1stTimeMummy]

Hello all,

I am new to Mumsnet & also a first time mummy!

I wanted some advice off any parents who have experienced the following:

My 15 month old toddler hasn't really been a very good sleeper day or night (mainly night times).

We recently changed him onto 1 nap & it's caused him to wake in the middle of the night & not resettle for around 3 hours!?

We haven't done any sleep training with him which may have had an impact & we do rock & comfort him to sleep.

This is our day routine too:

6/6:30am wake up & milk (at times he has been an early waker around 5am)
8am breakfast
9:30am snack
11:30am lunch
12-2pm main nap (can wake after 45m-1h & will need settling)
2:30pm snack
5pm dinner
6:00pm bath time routine & 6:30pm milk
7/7:30pm bedtime (sleeping at this stage)

My toddler can't self soothe by himself either.

Hope to hear back from what you may suggest or even experienced yourselves!

We have a 15 m/o and that's similar to our routine but he naps 12-3.

We did start sleep training when he was about 9 months so he settles himself. Took a few nights but he settles himself for naps and night except for when he's poorly etc.

I'd probably work on the self settling and possibly introduce a short morning nap of 20 mins (we've just dropped that one) if baby is still overtired and waking.