Hello !! yes , overactivity of mind crosses the barrier then sometimes serious issues may result. yes this is a health problem. To keep control over mind ,you have to engage your mind in your work, hobbies etc. Never stay idle , always think about productivity and postive thoughts and never think in negative way. Do some relaxation excercises and meditation such as yoga, dhyana, pranayam and anulom-vilom. Besides this maintain a regular daily routine and try to stick to the routine. Share your thoughts with your partner or close friends . avoid taking alcohol/smoking. take balanced diet with plenty of fluids. take some time to thank God, pray/ worship and maintain positive attitude. You may consult a psychiatrist for medication if the above mentioned nonpharmacological techniques do not offer much help. I hope this answer would be helpful to you. any further questions are welcome.