My Doctor Says I Have Anxeity But I Do Not

My doctor says I have anxeity but I do not believe anxeity is causing these symptoms just yet. I have heart palpitations all the time and I can see it beating when I look at my chest I also have abominal pulsating and trembling and tingling of hands and legs sometimes and can't remember like I used to and can't concentrate and I feel very weird and I'm 15