What's wrong with me?

I'm 17 years old and my weight and height are normal.
For about 3-4 months, I would go for a few days without eating lunch, breakfast, or both. Not to lose weight or because I had an eating disorder, but because I felt like I didn't need to. It became a habit. Then a few weeks after I started doing that I started feeling very exhausted for seemingly no reason, no matter how much sleep I got. Then my chest had this weird squeezing feeling, but I assumed that that was because I had been doing too much physical labor and it was just my muscles. I kept trying to figure out what was wrong, but I decided that I should just ignore it. Then one night, I realized that that squeezing feeling I had in my chest was getting worse. I quickly ate something, knowing that it was probably because I wasn't eating enough. Then I had an ache in my chest along with the the squeezing feeling that went up to my left shoulder. I tried to tell someone, but when I opened my mouth, words would not come out. It was like my mouth was paralyzed.
I became in denial about it for maybe 10-15 minutes, hoping that I didn't really have a problem. But it got so bad that I thought I was having a heart attack, and honestly I wouldn't be surprised if I found out that I was even now.
After this, my legs started shaking involuntarily. They only did this when I sat down and stopped moving them. It was like a seizure only in my legs. So finally I showed one of my siblings what my legs were doing, and they told my parents. My mom took me to the hospital right away, because she said I looked really pale. When she asked me questions, I just looked down, sort of confused and sometimes I still couldn't move my mouth. I was having trouble breathing as well, which got worse when I tried to speak or walk.

When I got to the hospital, I spent about 5 hours there. I had a lot of tests done, but everything turned out to be normal, except my heart rate was too high and my heart would skip a beat (I don't remember what that's called). My legs still would start shaking (sometimes kicking) by themselves at the hospital, but no one could figure out why. I could also feel my heart beating in my chest.
The people at the hospital assumed that I was under stress and just was nervous or had anxiety. I felt really calm and peaceful at the hospital, but they still kept thinking I was nervous and afraid. I did feel slightly confused and kept forgetting things. I thought secretly the whole time that something was wrong with my heart, because that's what it felt like.

Now I eat 3 meals a day again every day because I'm almost 100% sure this was caused by not eating enough. But this morning I felt my heart beating hard again, so I checked my pulse and it was over 100 after resting for a while. My normal resting heart rate has been about 70-80 for the past few years. Then, I rested and stayed still for 10 minutes and checked it again, and it had gone up to about 120 (I think it was a little higher than that actually). I started having slight trouble breathing a few minutes after.

I feel okay now, except I have a headache. I just checked my pulse again and it's around 100 still, and I have been sitting for a while. So does anyone have any ideas as to why all of this is happening? No one can figure out why and I wish it would stop because it's interrupting important things and becoming a distraction.

Please don't tell me to see a doctor, I already have and they don't know what's wrong either.