What Causes Acidity, Heaviness In Head And Missed Periods?

Sir, I am having acidity since last 4 days(with no severe abdominal pain).It gets worse at night when i lie down.I am also experiencing some sort of heaviness in my head.Although, i am not having any problems as far as bowel movement is concerned.my periods were supposed to start 5 days ago ,but have nt yet.i am afraid if there s any correlation between acidity and missed period.