My anxiety

lately I’ve been having so much anxiety that is keeping me from focusing on school and on my mental health. A lot of my anxiety is triggered in social settings like in large crowds and parties. Lately though I’ve been feeling a lot of anxiety over things that honestly I shouldn’t be anxious for but I am. Everytime my friends don’t text me right away I either think they are ignoring me or they are dead. I keep having visions of people dying in horrific ways and me killing myself in many ways. I’ve been trying to bring it up to my therapist but honestly I don’t know where to start. I need help, please