At some point I had to take medication where one of the known side effects where higher blood pressure. I also noticed a significantly increased blood pressure

At some point I had to take medication where one of the known side effects where higher blood pressure. I also noticed a significantly increased blood pressure every time I took this medicine. This continued until one day someone knocked the door just before I took my pills, and I still got the same symptoms while the pills where safely on the kitchen. I then realised my brain had played games with me and since then the side effects disappeared. ...and I consider myself somewhat rational.