Hi, I am taking generic form of concerta, have been for a little over a year. Lately I am feeling head pressure that I have not experienced before. Is this the drug or something else? I wondered if I wasn't drinking enough water but I have been doing a healthy diet program that requires 8 glasses of water a day and am doing that regularly plus eating whole food diet with vitamin supplement and b complex. With little or no refined sugars. I am wondering if the medication is all of a sudden causing this. As of yet I have noticed no side effects within a years time of use. I even have low blood pressure.