Coping with health anxiety

Hi Guys

im new to this forum and If Im honest Im at a very low point in my life which is why Ive joined here just looking for some support. Ive always had health anxiety from the age of 15 , however it was never that bad and I was always able to brush it of no issues. Last November however my best friend who was basically a sister to me died very suddenly of a stroke only at the age of 22. Since her death not only am I struggling to come to terms with it my healti anxie has hit rock bottom and I cant seem to come out this cycle. As I write this I am in tears which seem to be a everyday thing for me . I have had all these weird symptoms since and just cant helpbut think this is more then anxiety . Ive also had this issue with a mole on my arm even though three dermatologists have stated that they are not concerned including two private ones , I cant help but think that its cancer and that I am dying . have also been having stomache issues and again Im convinced that i am dying . I know it c sound ridiculous , Im only 22 and before my friends death I was a happy , social young girl who was so excited for the future. Now Im a complete wreck I have to force myself to act like everythings okay when most nights I cry myself to sleep. My relationships with some close people are getting worse and Im under performing in my job that I once loved so much . If anyone can offer some positive words of support I would really appreciate it.