16 and Really bad anxiety..

I've been diagnosed with severe anxiety. Is worrying about my health and future because of my anxiety? Im constantly thinking there's things wrong with me. I've always been someone who wants kids when I'm older. I keep thinking it's never going to happen that I'm never going to be able to have children. I don't know where it's coming from. Deep down I know there's nothing wrong with me but I can't stop worrying about it and it's driving me insane. I shouldn't be worrying about things like that at my age but I can't control it. I'm trying to focus on my life, I want to get an Apprenticeship and make a start on my career but all I seem to keep doing is worrying when I'm going to have a baby. It's crazy I know. I just want it to stop I want to focus on my career but this is getting in the way. I can't see a therapist until I'm 17 because in the UK when you turn 17 you have to see an adult therapist and as I'm 17 in a month they said I should just wait until then. Is there any way I can stop these thoughts in my head and stop all this worrying until then? My anxiety just makes me constantly worry about my health and future and it's driving me crazy it's mentally breaking me down..