according to your question it is observed that you are still un married ,see premature ejaculation
can only be positive when ejaculation takes before intercourse, time is a important factor only by masturbation
you cannot label that you are suffering from premature ejaculation besides that your question is still incomplete,like after erection how much time does it takes to ejaculate in my opinion you are not suffering from any disease,if still in doubt you can consult a normal physician,masturbation is not related to your hair or memory loss
,keep yourself healthy by regular exercise and healthy food.
if still doubt you can call me. thanks