So I was on ritalin for studying purposes due to me having massive workload. I used to take 15mg almost every day (For a year) after work to study. I then stopped it after studies was completed and after 3 months I started getting panic attacks and felt the need to shiver. I was then put on stresam to help with this shivering and it seems to be helping. But I'm just thinking if ritalin was the cause wouldn't I start having these issues like 2 weeks or so after stopping it as opposed to 3 months?