Hugs Lily. Sorry, I was out all afternoon due to my home inspection. Try not to stress too much if the first nap goes awry. In cases like this, I wouldn't cap a nap unless it's running really late in the day. Usually if my first nap is bad, then I hope for a better 2nd nap so that we can maintain a normal bt or do a slightly earlier bt (just a hair earlier). I'm thinking that your DD has some set biorhythms, so she's expecting BT to occur at a certain time rather than after her A time has elapsed (does that make sense?). I think this may be why the really early BTs didn't really work but she was waking early because that's what her body felt was right. Having said this, let's hope that her 6 am wu habit has been broken!
Ok, let's take a step back and see where we are at.
WRT WW, there is one at 37 weeks. Is she clingy and fussier than normal? Along the same lines, is she crawling yet? Sorry, can't recall. I'm wondering if she's starting to practice in her sleep again so that means to give her lots of opportunity to practice during the day.
Her fever is gone right? I guess she still has a rash but is that bothering her?
Also, has she cut her teeth yet?
I'm guessing her short morning A was due to the nw last night which may be in part due to hunger but may be also developmental stuff? I think she's around the age for a WW so that may be throwing a wrench into things.
I would start to increase her A times back up to where they were before (ie. 3 hr 15 or 20 min or so) as long as she's no longer sick. to address the teething, I'd either medicate prior to naps and BT if you think that she has discomfort. Due to the WW, you may need to be close to her while letting her practice crawling, etc. She'll need the reassurance of having you close by. Since she may have a WW and teeth / illness, I'd let her have 1.5 hrs of really active floor time but then end 30 - 40 min of calm activities so she isn't too wound up to nap well.