recovering from potassium deficiency is very slow?

Potassium level is up and down for 3 months now,it started when i was taking simvastatin for 1month for my choles serum,i didnt eat well coz i was afraid of my choles. I exercised too much w/o proper meal at the same time taking simvastatin,checked with neurologist then my potassium is 3.2 mmol/l ,next lab was normal 4.1, then 4.2 again,i stopped simvastatin,then cramping stop too..eating proper meal as my choles now normal,but till now easily get tired then dizziness will follow,i keep drinking energy drinks with potassium 11mg..is it ok to drink it everyday?is it normal that recovering from potassium deficiency is very slow? Thank you and looking forward to hear any advise...