Fussy 12 month old after starting cow milk

My baby has been breastfed and eats table foods. She recently turned 1. Starting Sunday, I started cutting back majorly on breastfeeding, and instead offering 1/2 cow milk mixed with 1/2 breast milk twice a day. She will drink about 8 oz of that mixture in a day (so only about 4 oz of cow milk spread throughout the day).

She hasn’t had many bottles throughout her life, so drinking milk out of a sippy cup is a new experience for her as she’s used to drinking it directly from me

She also just got her 12 month shots yesterday. She had a low fever last night and didn’t want to move much which isn’t like her. No fever today but still fussy and wants held lots

I’ve only been breastfeeding her before her nap and before bedtime. I plan to cut that out in a few weeks, trying to slowly cut the feeding sessions down as she was still breastfeeding 10+ times every day

She will have her moments throughout the day where she gets upset when she is asking for milk and I tell her no to directly breastfeeding (and of course offer a dif snack or a sippy cup of cow/breastmilk). But she is doing better than I anticipated with not breastfeeding as much, bc she was really obsessed with it lately and would come to me and try to breastfeed when she was upset trying to calm herself down

But she’s been super fussy lately. And awake a lot at night. She hasn’t always been the best sleeper, but she will usually get herself back to sleep within a few mins. Every once in awhile she will be up a lot at night, so it’s not too unusual. But the last 2 nights she’s been up a lot a night. It isn’t usually 2 nights in a row like this (i quit breastfeeding her in the middle of the night several months ago, so it’s not like she’s crying expecting milk). Nothing in her bedtime routine has changed

She wants to be held a ton all day too, doesn’t want set down

What’s weird too is her fussiness seems to be in phases. She won’t let us set her down for a couple hours, then all of a sudden be super happy for the next hour, when nothing has changed

It’s also hotter weather so I’m wondering if she’s not sleeping as well bc it’s been warmer? (I have the fan on for her)

And as I said she hasn’t slept well at all last couple nights so probably behind on sleep..

So I guess I’m wondering if anyone thinks the cow milk is the problem. I remember going through this with my oldest having a hard transition and got really constipated at 1 when starting cow milk. Does it take some time for babies body’s to adjust to it? She has had dirty diapers since the transition, but did skip a day of having one. She did struggle to go a couple of the times too.

I should add she has lots of yogurt and cheese, yogurt is a fav food of hers so she definitely does eat a lot of dairy already

She isn’t having a ton of cow milk at a time either, she kind of sips on it in the morning and later afternoon.

We also have a lot more she’s gone through lately- the shots, warmer room at night, not sleeping as well, cutting down majorly on breastfeeding, so maybe a combo of all ?