15 days is excellent, Mav! I think most of us have felt the way that you do in early sobriety. I think it is our brains' way of trying to recalibrate, especially if it has been a long time since you have last tried to quit.
Talking to your doctor is an excellent idea, though, just to share your feelings. One reason doctors cannot diagnose folks with anything while someone is drinking is because they have to rule out that drinking is the cause. I'd say if you have struggled with something in the past, you could be masking it, but if not, it might just be the good ole blahs. When I felt that way I always tried to do nice things for myself, whether it be a great meal or just whatever. Extra sleep if you need it. A walk if you're ready. What you might also be experiencing is that feeling of 'what do I do now?' with all of this extra time you have now that you are not drinking and recovering from hangovers. Just know--above all else--that it is totally normal in early sobriety. Give yourself HUGE credit for 15 days. If you can go 15 days you can go a lifetime. You do NOT want to start over on day 1--none of us does. You've got this!!