So was curious if this was unique to me, or is a universal experience. As soon as I start thinking about taking my medication in the morning, my heart starts racing before I’ve even taken the bottle out of the cupboard. Then I take it and my heart continues to race for about 45 to 60 minutes before it calms down. It doesn’t hurt, but it’s unpleasant and kinda spoils my mornings. Anyone who has ever consumed way too much caffeine in a short period of time can relate.
You should probably speak to your doctor/psychiatrist about this, but it sounds like it might be anxiety? Oddly enough Ritalin calms my anxiety as well as helps with my ADHD symptoms. When I was on short acting Ritalin I’d be on the anxiety roller coaster- gone when the meds were in effect, then heart racing as they tapered off. The calming down you describe might be because of the dose kicking in?