What Causes Lumps On Scrotum And Shaft?

I have itchy bites (i think are bites) on thighs, lower abdomen and even some on my hands. My main concern though is the lumps on my scrotum, and also one on my shaft. My doctor has ruled out hpv or herpes when i originally showed him, but since then more have appeared, the original ones have gotten smaller but still itch when irritated. The lumps do not itch unless i scratch them first, and ttwo of them are probably one cm in diamter, the other two are now irregular shaped and probably half the size and the one on my shaft looks like a small pimple without a head to it. My foreskin also sort of has a itchy sensation to it, but not itchy enough that it forces me to scratch it.