What Causes Dizziness Along With Frequent Urination?

I have been dizzy when getting up them it went during the day and the dizziness came back during the same day had this for 3/4 days not all day and then it went i was ok for 2 weeks and then now I have terrible lower back pains with nights sweat and urinating during the night twice sometimes do you think I have something serious diabetes or could I have leukemia ?