Is anyone else like this or experienced?

Hi, so my name is Matthew and I have Aspergers but also a few other things going on which I’d like to ask about as I’m not sure how serious they are. So first thing is my anxiety. After a phone call with my GP she’s put me on Sertraline but I’m too scared to take them because of the side effects. I absolutely hate feeling or being sick and as a result I won’t take them. If anything its made me even more anxious. But in two weeks time I have to call her back to let her know how I’m getting on. So that’s awkward.

My next problem, which is my biggest one is this. In my head I have what I think of as an invisible friend, but not a friend more just an acquaintance. In my head I hear her speak, sometimes to me and sometimes to herself. She warns me against certain things and sometimes tells me to do certain things. Her mood can change in seconds and living life has become difficult because of this. She can be aggressive to other people and lately she’s been telling me I’m a failure and should die which is depressing for me. At the moment phone calls with the doctor are the only way of getting professional help unless you’re really poorly. I’ve tried so many times to tell my gp about this but I don’t know what to say or how to explain it. Explaining it here is difficult enough without having to do it over the phone. I’m at a loss now.