Hi there and welcome to BW forums
Short naps are common at 4 months so you are not alone in this unsettled routine of 45 min naps. My own DS was sleeping independently before the 4 months regression hit and we also ended up is 40 min naps 4 or 5 of them each day - it's exhausting.
One of the common problems is that the A time has not been increased rapidly enough. A times increase quite significantly and quickly at 4 months (and to 6 months) and if you miss the window it can feel like LO is forever OT having short naps but what is usually needed is a longer A time because LO is UT (under tired).
The irritation she is showing when you start the WD sounds to me like she is trying to tell you she is not yet ready for her nap.
Guidance A time is 1hr 45 to 2hrs at 4 months. You don't say how long your current A time is but I'm guessing you might be too short or reducing it to try to make up for the lost nap and in an attempt to avoid OT.
If you current A time is significantly shorter than this guidance time then I suggest you increase in steps over a number of days rather than one big jump in length. You can increase by 10-15 min each day until you get to a suitable time.
If she continues to be irritable with the longer A time you can either stick it out in her room until she goes down (stay with her, shush/pat as needed, pick up as needed) or you can say "ok looks like you are not ready yet" take her out and try again 10 min later.
You can also try a W2S (wake to sleep) at the 40/45 min mark, here is a link, please see naps option 1 where you begin patting before the usual time she wakes.
https://babywhispererforums.com/index.php?topic=223809.0This can help to sleep train as it teaches LO to nap longer. During the 4 month regression though sometimes they do just have short naps as part of the developmental phase, if you can W2S to help extend the nap you will avoid OT. If though it becomes too much for you then you can choose to do it just once per day for example or whatever you can manage. Some people decide to just accept the short naps during this phase as they can't cope with sitting in a dark room patting all day and wait for the phase to pass which is around 6 months.
if you record your EASY times you can post them here with an update if you like?
We use a format like something like this:
WU 7
E 7
A 2hr
S 9 - 10.30
E 10.30
A 2hr
and so on... include:
BT ( bed time)
DF (dream feed) or NF (night feed)
NW (night waking not for hunger)
and through to the next WU
Include any brief notes about what you did to resettle (eg W2S or shush/pat etc) and LOs mood (fussing, resisting, crying hard, waking happy etc)
I used to dreamfeed at 11 pm and 3 am. Last night for example she woke up at 1.30 am and 4 am. Do I s/p when she wakes up at night?
sorry I'm not sure here if these are additional NWs. did she get her feed at 11pm and 3am or have you stopped the 11pm dream feed??
If she needs feeding just go ahead without trying to resettle. If she's been fed then yes you can use shush/pat or pick up if needed to calm her and help her back to sleep.
And she has been waking up at 5 am instead of 6 am.
Not sure where in the world you are, I know lots of us in the UK are getting brighter mornings as Spring is here and this can have a big impact on WU time. Thorough black out can help. My own DS has 3 layers of blinds and blackout in his bedroom so that he doesn't wake early. early waking is not always routine based.
hope this is of some help.
