I Have Been Getting The Feeling Of Being Pregnant

for the last few months iv been geting the feeling of being pregnant , iv got children already so i no the feeling and the symptoms of what i suffer during pregnany seem to have reapered i.e heart burn itching of the skin tierdness etc but i do hae the implant in my arm, i v been suffering with really bad headaches aswell and a sudden gain of wieght i spoke to a doctor at my local surgery about the headaches and she diagnosed me with chronic miagrains but when i told her how i was feeling she basically laughed it of saying it was impossible.... please can u help me