Prediagnosis as a young adult kinda

I’m a 20 year old female with ocd and gad (generalized anxiety disorder) who has been a spitting blood since 2025, I was told it was an infection over the phone after I coughed blood for the first time my gum bled severely when I brushed and sucked my tooth within the same time of the blood cough I do have dental issues. Fast forward I’m having more blood episodes, extreme chest tightness I had spat blood after waking up, i spat blood after throwing up in my mouth, i spat blood after a shower, I spat blood when hunched over and I spat out some dark colored mucus, I seen what looked like blood on the collar of my white shirt I’ve had extreme gerd since 2019. This year I started freaking out about lung cancer and going to ers, calling 911, crisis mental health team came over, during my er visits my hemoglobin was like 14, my calcium was a bit high at 10.5 my ionized calcium was 11.1 anything abnormal stabilized itself but I heard cbc isn’t reliable for health status I did get two chest x-rays one with 2 different views and they didn’t see anything just my scoliosis. I kept having extremely low oxygen readings at first it would say I was 81, 78 then would go up to 100, or from high oxygen it’ll go down to 89 then say “?” Or signal poor but I’m afraid that was real hypoxia? I don’t get extreme low readings anymore but one of my thumbnails turns purple everytime I’m in my bathroom. I got a cbc again in may, the 28th and it said I had an immature gran of “1” hemoglobin still normal, then beginning my of June I spit blood again and it didn’t stop as quickly as the other times, I got to the dr get a cbc and my hemoglobin had dropped to 11.5 from 13.2 in a week I was not flagged as low, but my ferritin was 23 tibc high, iron normal, and now we’re here..I’m getting a chest ct scan with contrast and convinced I will be diagnosed with stage 4 lung cancer and will die soon, also convinced I have svc syndrome for feeling pressure in my ears when I bend my head down in a squat plus being able to feel the back of my neck vein when I raise my arm and eye swelling in the morning. my knee is a bit swollen on the left side so I’m also worried that means I have synovial metastasis causing effusion. Does anyone I mean anyone please have any words that can make me think in a different way I can’t let this go even when I don’t have blood spits or weird oxygen readings currently and I’m taking iron