Hey, I'm 17 and I'm going through the same thing. I went to high school last year just to quit mid-year for several reasons - that being living 35 kilometers from school, bad teachers, intensely difficult math and me being lazy. So I just stayed home, no friends or anything because I recently moved in a new town. Got a gaming desktop and started playing games the entire time I was awake. It was winter so I had nothing else to do really.
It all started when I was warned about brain tumors, I went insane the first day I read about it and swore I had one, I was dumb. That caused me to have health anxiety til this day. For about 3-4 months I was anxious about brain tumors, then I got over it, though I had REAL symptoms of a brain tumor back then, they all went away. A few weeks without any health anxiety I searched up "lack of activity" and got heart disease, new topic to cry about. It was worse because I had been inactive for a year, there's always a certain risk factor that makes you anxious about something, for the brain tumor it was excessive use of a mobile phone, now it's activity. Anyway I started getting chest pressure and shortness of breath, one day I triggered a panic attack and called an ambulance. They said I was healthy and left, bp was crazy high tho. Went to a doc, said I was healthy. I felt relived and happy but the day after I felt really depressed waking up, I got constant palps for the next week and I went insane.
I tried to ignore it all, I couldn't. I started getting this dull shivering acne all over my left side of the body, it started in the left abdomen and radiated upwards to the chest. It went worse when I got emotionally stressed to a point that it would feel like my heart stopping. Asked my friend "Hey, i'm having this pain, probably a heart attack, right?" he said it's possibly dangerous and that triggered panic again. I called an ambulance again. The moment they stepped in the pain went away, it was still there very mildly though. And again, I'm healthy and I wasted their time. They said it was all in my head which is just stupid. I felt really embarassed for calling an ambulance again, my neighbors must think my family is insane. The pain persisted for a day or two but it didn't feel like my heart at all, I didn't feel anxious about it. From that point everything went better, I was happy again, then the pains came back. It's always a new type of pain every time too. Pressure started 2 days ago after some excercise, felt like something squeezing my heart. This has been constant and is right now. Something sharp pain that I would feel in my shoulder. My back is sore all the way and feel like I need a strong massage. My nerves are so clogged up when I rub my back I would feel it in my arms and they also go numb. Both arms and legs have sharp radiating pains. Rececntly got pains in my throat and mouth ceiling, to my nose and leading to a pressure headacne above my eyebrows.
I recently had so many symptoms it felt a heart attack - chest pain and discomfort, dizzyness, leg and arm numbness especially in the left arm, sore back, you name it. Almost every symptom indentical to a heart attack. Worst panic attack I've had, it's 4:41 AM, went to sleep at 9AM yesterday, trying to fix this pattern as it always gets this bad. I was close to calling another ambulance, but I didn't. I feel better now, still dizzy though.
As you can see I'm in a worse condition as you. Even though it feels like hell right now it will get better eventually, it was so good to be happy again. Hope you get better.