over masturbation and short ejaculation time

i used to do masturbation almost everyday for last 12 or more than that years. now i am married for two years. now i am having problem of my timing. i come very first..within 15-20 second of entering into her. i was thinking of going to see a doc. is it because of that over masturbation? should taking medicine would help me?
please note i do whole lot of work in office and it leaves me in tiredness. is that related with the sexual matter?