I suspect that your dose is too high. Other psychiatric medications, like some SSRIs, can help with weight loss but if the dosage is too high, they contribute to weight gain. I also wonder whether the BP increase is from the weight gain alone or from the ADHD medication.
This could also be a rebound effect. You should talk to your prescribing doctor about potential options. (For example, I take a higher dose extended released pill in the morning and a smaller dose ER at lunch time when I break fast so that my treatment is smoothed out better and I don’t get rebound energy at night.)
Again, talk to your prescribing doctor.
That’s… funky. Definitely talk to your doctor, perhaps after talking with a pharmacist. They usually know all the side effects, alternative options, etc., and you might be able to talk with your doc and propose something the pharm recommended. I have a cupboard full of Adderall I stopped taking because of severe dry mouth (it kept getting delivered b/c I kept forgetting to cancel it), but when I was on it it killed my appetite almost completely. Most stimulants will do that, so definitely talk to someone.
Sounds like you are using concerta. Perhaps ask the psych to have you try out elvanse/vyvanse? I take 70mg elvanse every morning even when fasting and have no issues. I didn’t do any fasting while on concerta so can’t give any anecdotal comparison though. I do know that concerta and elvanse have very different mechanism of action for the delivery of the drug.
I have found that with ADHD meds, fasting initially is made a lot easier but with any major stress thrown in there, eating becomes like a nervous habit and a comfort blanket. Vyvanse has been prescribed off label to help with binge eating but we still have to be mindful of anxiety management techniques and recognizing when we’re turning to food for comfort.