Red/pink Spots On Chest, Neck, Lumps On Breasts Appears On Or Before Periods, Itchy. Reason?

Hi. Over the past few months I ve been starving myself because of weight issues. I realised I had to stop because I had developed a surge of red/pink spots on my chest, neck & nape area. I hadn t realised they were that bad because it was itchy & provoked me to keep scratching until I stopped when I saw the spots forming. I also had a lump on the side of my neck.. Thinking it was a swollen gland.. Then fearing the worst that it could be an abscess etc. My Doctor said it was actually a viral infection & prescribed me some allergy tablets to treat it. I have managed to lose some weight.. Yet have also gone back to very bad habits; like purging everything I eat.. Bulimia is something I ve been going through since 2009. I just feel the need to puke all the time. I understand that my periods have been somewhat irregular which is down to not eating healthily or on time. I skip breakfast & eat in the evening which leads to more purging. I drink plenty of water to compensate fir the effects. I ve also noticed tiny lumps in my breasts. Sometimes my right.. Sometimes left.. Even feel very itchy.. Then tender. These patterns have been developing around the time of on it before my periods. I once felt a blunt pain in my lower abdomen.. Then a few sharp ones on the inside of my vagina; feels like the pain is coming from the left side of the ovaries. These sharp pains occur from time to time. Sometimes they go away.. Then come back again.