A potassium level of 2.8 mEq/L is low and requires professional medical attention, while your sodium level of 135 mEq/L is near normal. A single dose of potassium chloride is rarely enough to correct this deficiency, as replenishment takes time. Also, low magnesium levels can sometimes block potassium absorption. Since you take olmesartan and tamsulosin, it is crucial to consult your doctor promptly rather than self-medicating. They will safely manage your electrolyte replacement, likely check your magnesium levels, and monitor your blood pressure. Do not panic; this is highly manageable with proper medical guidance and close monitoring.