Hi, I am 21, I am french so my English is not perfect sorry. I have health anxiety and OCD. I always felt worried about my health, I always feared to die. Last week I went to the doctor to check my heart. My heart is normal but a little to quick because of anxiety. I am under medication. Since then I feel lightheaded. It last a few second and it happen very often throughout the day. It also happen at night. I woke up at the middle of the night and it feel like I am dying, it worry me a lot. I thought it was because of my medication so I stopped it but the feelings are still here. I am constantly worried, scared that it might be a cancer or a cardiac issue. It is ruining my life. I don’t want to take antidepressants. 
Have you ever experienced that ? Is it anxiety  ? 
I am going to the doctor soon, should I worry about my health ? What can I do to stop feeling lightheaded ?
Please help me it’s ruining my life