Can baby drop then go back up?

38 weeks and 5 days here. Over the weekend I was really not feeling well. Couldn't breathe, nauseous, couldn't sleep for the life of me, couldn't get comfortable, and Braxton hicks like crazy. Then Monday night and Tuesday I felt great but felt more pressure in my vagina. Now tonight I can't breathe, uncomfortable, etc. I'm wondering if we experienced lightening or engagement for the last few days which made me able to breathe and not feel nauseous. But now she's moved back up, nestled back into my lungs and stomach, basically no longer engaged?? Is that even possible?