Rode for about an hour yesterday and it felt a bit better. I think I was tensed up because I was nervous the first ride out. I do think that maybe my handlebars need to be tilted up slightly. I am assuming that's a reasonable adjustment? They don't feel too far, I just noticed that when I sort of pushed up slightly on my fingers so I was maybe half an inch higher, things felt perfect to my back.

But I probably do also need to work on core strength.

I'm going to try to schedule an adjustment for next weekend and give it another week to play around.