Yes, the routine will look different every day. It's more about going from the time she wakes up, then she has roughly the same A time in each EAS cycle, then she eats about 3 hours apart...that kind of thing. Your days can be "off" by 30 minutes compared to the day before or after...and that's completely fine
For us, when DS was 3 months, some days he would wake at 7, some at 7:15, some 7:20. We never let him sleep past 7:30, though.
At her age, most LOs are doing something like this (please remember, this isn't a schedule, but it shows how the routine repeats itself throughout the day):
Awake at 7 and eat
S: asleep by 8:30 at the latest (note: this assumes your LO can do 1h30 of A time, but she should be able to do between 1h20-1h30 by now)
E/A: 10
S: by 11:30
E/A: 1
S: by 2:30
E/A: 4
S: catnap for about 40 minutes between 5-6
After she wakes up here, do bedtime routine and feed
S: by 7:30 (maybe 7 if she needs it)
DF: between 10 and 11
Looking at what you posted, it sounded like she was only awake for 45 minutes (11-11:45). I know she was probably yawning, but sometimes babies just yawn
I had to stop relying on DS's yawns so much and go more by how well he napped. Once I figured out, oh, he could do 1h25 minutes and get a good nap afterward, then I started getting all his A times to that. I never let him go to sleep more than 10 minutes early for his naps. So, it's kind of working backwards. Also, by knowing how much A time he could do, that allowed to see his REAL sleepy cues. Now I know that is he's constantly fussy, doesn't want to be held any other way than me standing up with him, then he's getting ready for a nap.
Do I follow her cues and put her down at the first sign of tiredness or put her down each day a designated time after her feeds?
You'll get better at following her cues, and while her naps will be about the same time most days, set nap times are not good for young babies.
I think once you get her on a more consistent routine, that you'll see her nap issues improve. Or if not, then the advice we give will be more helpful because we'll have a more solid framework to go by
Hope that helps a bit.