Is it possible to become pregnant on the implant?

I have had the implant for about a year now, and never had any problems. I have a new partner and we have been sexually active every night for about a month now. I have had a period since we first had intercourse but it was different than usual- a lot heavier bleeding but no period pain as usual. During the past couple of weeks I have felt very sick, headaches, constipated, 'metallic taste' in my mouth, cramping in my lower pack and stomach and also incredibly tierd. I know that even if there was a chance of becoming pregnant these symptoms are incredibly early. I have also heard that the implant can make u have pregnancy symptoms, but I've never had these before. It is too early to take a test, im really tempted to put my mind at rest but I know if it came back negative it could be wrong because it is too early. Does anyone have any advice? Is it too soon to ask for a blood test at the Dr's, or is it too soon for that? Im going out of my mind, thanks.