Staph? STD related? Diabetes?

[Ali_Meows]

Hi all!
Wondering if anyone can help me diagnose an issue I've been having on my left forearm. This started about a month and a half ago from what I thought was a mosquito or bug bite or even just an ingrown hair because I do shave my forearms. It was just a small red bump that looked like a pimple and itched a bit. I picked at it and messed with it thinking it was a pimple. After several weeks of treating with Neosporin and other healing creams and ointments it has turned into a bigger spot which is a bit raised and has white scales on the top. It almost looks like psoriasis, which about 5 years ago I developed all over my legs and trunk, not in patches but spots like the one on my arm. I treated that issue naturally and it went away. Since then I've had random spots pop up here and there and go away. Maybe a week after the first bump, another bump appeared below it, and then about a week and a half ago another bump below the second. This last one seems to be the most infected. They are not itchy at all. For the past few days I have been treating nightly with Apple Cider Vinegar soaked cotton which I affix with bandaids. I started eating raw garlic today and adding tea tree oil to my treatment. When I take the bandages off I put Neosporin on them. Do you think this is Staph or something else? Ive also had unprotected sex with my boyfriend of 3 years who I found out was cheating on me. Wondering if this could be a STD symptom. I'm getting tested tomorrow. Im also having an IUD removed tomorrow which has caused me an array of issues as well as a 50 LB weight gain. Wondering if these could be Diabetes related sores? I had blood work done a year ago and everything was fine so I have not been diagnosed with Diabetes. I'm including a link to my pictures so you can see what I'm dealing with. Thank you!

https://drive.google.com/open?id=0B1O4_BNmqS-xaWFBbW1qR2VWNW8