Overdosed Topical Minoxidil now faced with palpitations

Two months ago I started minoxidil and I was applying a lot(5 ml per day). I am a 20 year old male. I basically applied a 4 month supply of minox in a month and a half. I stopped applying two months ago but now I heart palpitations that occur frequently during the evening and morning. I have visited a clinic and they performed a ecg(incomplete right bbb and non specific ST abnormality) and it showed something abnormal. I have yet to perform a echocardiogram and stress test, should I be worried?