I've had these tiny white(smaller than bumps)but bumps on the head of my penis & also my shaft, i've taken std tests negative, the bumps come & go?

Not STD. Miliaria?: This doesn't sound like any STD. I would wonder about miliaria crystallina (heat rash w/ temporarily blocked sweat pores) (google it for more info). The large majority of genital skin problems are not STDs. (There is a color atlas of genital dermatology. Of 290 pages, only 15 are about STDs.) If you remain concerned, see a doctor, preferably a dermatologist.