Today I felt much better. No more burning lungs, although I was breathing hard. Had a 19.3mph average today and didn't need to sit down to recover when I got to work. I also felt my comfort zone coming back, feeling right on the bike vs. being perched on a tippy stool like it felt like the first mile yesterday.
Still its strange to be riding ~5mph slower, but feeling worse than I did when going faster, even for much further distances. It is a reminder that when I get back to that space, that to get beyond it I need to feel as bad I as I do riding now.
Al