Hi I Am A 22 Year Old Female , 5.2

hi I am a 22 year old female , 5.2 in height and 7 stone in weight . over the past few months I have been very unwell due to range of symptoms that just get worse these symptoms are....severe lower back pain , fatigue, dizzy spells, blurred vision, sudden weight loss (was 8.3), loss of appetite , sore heads, difficulty with bowel movements ,low right side abdominal pain ,chest pain and side chest pain ,cough, swollen tender neck and lumps, lump about 2 inches inside vagina that is painful during intercourse, difficulty breathing ,throbbing tingling veins in my legs and easily bruised, I have a had thyroid,diabetes ,anemia blood tests done all normal but have low potassium .what could it possibly be?