You are on day 33 of doing something intensively that you haven't done before and your body is reacting. There is probably some compensatory inflammation.

You are young and heal faster than @snojones does. (And a lot younger than I!!! ). His "No pain the next day or no guitar" is probably a good suggesion. Some will argue that you should have a guitar in your hands every day! If you don't want to go a day without practice, when you have those days of pain, make it a very minimal workout.

Also for inflammation, there's always a brief round non-steroidal anti-inflammatory (NSAID's), like ibuprofen. Take it with food. And check with your primary care provider on this. Your body is warning you about what I said at the beginning. But you got the message so there nothing wrong now with quieting the message.