Hi so sorry you're having trouble! It is hard I know, especially with a baby that has reflux! To answer your questions:
*Is she trying at this young age to drop her second nap and just take a long morning one?
I really doubt it, usually the earliest they go to one nap is around 12 months. At 6 months, she might be going in the 3-2 transition though?
*If pu/pd isn't an option due to reflux, what should I do?
Have you tried shhpat? That is definitely what I would try. DS has reflux, and when I sleep trained him 3 weeks ago, I tried to comfort his as much as possible in his crib, and only picked him up if he was really distressed to not aggravate his reflux. Basically you comfort them in the crib but you allow them to fall asleep independently. When I first tried, it was difficult because DS cried a lot, but it was one difficult day and then it went better, and I felt good knowing that at least I was there to comfort him. At some point I would just keep my hand on his chest to let him know I was still there, but anything I tried made him more angry. So you need to try to find what will soothe or reassure your LO - singing, shushing, patting, gentle pressure on his chest, etc.
Also, I notice that she's 6 months now, could she possibly be going through the 6 month growth spurt? That mgiht explain why she was down to only 1 NF and now is waking up more?
Could you write down her EASY? Having multiple NW's and difficulty going down for naps can also be a routine issue.
Also do you really feel that her reflux is controlled? The new meds are working well you think? There can also be reflux flare ups during teething, illness, or growth spurts so that might be why she's more uncomfortable lately?
Difficult to tell if this last week the issue is pain... I'd think if the ibuprofen really makes a difference, then it is definitely a strong possibility.
About the OT cycle... she probably is, do you sometimes try to APOP a nap during the day so that she gets a good rest on those days she short naps? That's what I would always do when DS had reflux. it did help us make it through the day. Then we tackled sleep training and for 1-2 days he got more tired, but being able to fall asleep on his own really helped him to take longer naps and he was then able to get out of that OT cycle.
hang in there, I know all my friends too did CC and CIO and they think I'm crazy for being against it, but I think there is definitely more gentle methods you can try that will work! we'll help you get there