Anxiety about dvt. can anyone help?

I have a phobia about getting a blood clot and dieing. I just read this story at my work about a 15 year old girl falling off her bike and getting a fracture and a blood clot and having a stroke. I've. Had this phobia since I was pregnant almost two years ago and I can't seem to shake it . I've had d dimer blood test ultrasounds on my legs and physical and I've never had one. I'm 22 no medical problems ect. Should I worry? In most cases would there be symptoms of a blood clot. I feel like a lot of people are unaware of the symptoms so that's why they don't get into the hospitalin time. Please help my worrying brain