Low Potassium In Eating Disorders

Hi, I am wondering if anybody can help me.... I have had eating disorders on and off since I was 10 years old and although I have been offered a lot of help, I was never in the right place. I am currently planning my wedding (it's in 7 weeks time!!!), selling my house, moving jobs and going through fertility treatment! This has unfortunately brought with it a really bad period of bulimia for me, I am struggling to keep anything down, this includes water..... I have over the last 2 weeks had some strange symptoms, a feeling of tingling/pins and needles in my arms and legs, particularly my hands at non specific times. A feeling that my heart is beating differently, faster and then it almost feels like it skips a beat??!! I know it sounds stupid, but the only other time that I have had similar problems is when my potassium was low, through the bulimia. My doctor did a full check on my blood 3 weeks ago, but the potassium result was "stale"?? Does anybody out there think it might be potassium or is it something harmless??? Thanks in advance