I explained to the security that I had undergone a hair transplant the day before, because I had to pass a liquid, the graftcyte spray with me and keep applying it every hour or so (even on the plane). In the US the person who searched me was very kind and didn't ask me to remove the bandana, although I didn't have any problem removing it. In Amsterdam (intermediate stop) I was asked to remove it, in order to pass the search point and I removed it, and told them that I return from HT and they looked me very in a very strange way, as they didn't expect it. I believe you should do the same: don't even care about them as you will never see them again.
Also regarding the flight: if you sleep seated for 10 hours, I think this is the best sleep you can have against possible swelling, actually I believe it helped me a lot because my head was higher than my body at all time.