I don’t know when you started the vyvanse but I would start by checking in with your psych provider and see about possibly increasing your dose. I started at 30 mg and I remember it helped for a bit and then it seemed like I was struggling again. Anyway I quickly had to go up to 70mg that’s the max dose and been on that forever and it works good. I also had to add a short acting Adderall 20 mg at 3pm because I could feel it wearing off around then. I don’t always need the extra 20 in the pm.
I also know whenever I used to start Back to school I typically stopped exercising, slept less bc of studying and didn’t eat as healthy or mindfully. Those things will contribute to feeling like the vyvanse isn’t working as well.