I'm tired of being in pain and not knowing why.

I'm 17 and a year ago i was in normal health for the most part i had a few issues with it when i was younger but nothing that was long lasting other then some gastrointestinal problems. This year has been nothing but struggles though i started getting headaches that would be constant throughout the day and sometimes end up in full on migraines, after a month i was able to control it with some vitamin supplements but things only got worse from then on. My stomach issues started coming on worse then ever acid reflux with almost every meal and eventually i couldn't hold down anything, when i went to the ER after not holding down any food for 3 days i was diagnosed with gastritis given some anti nausea medicine and that was it! the medication worked for helping the nausea but not the vomiting while its settled down a bit i still can't hold down any food some days and ill have severe stomach cramps. In the middle of dealing with that i started getting horrible wheezing and breathlessness i had minor asthma as a kid so thats what my doctor said it was but it hurts so bad and my inhaler hardly helps when i get in bad coughing fits, whats even worse is every time i have gone in to the doctors my lungs have sounded just fine even if i have a coughing or wheezing just the night before. Finally the most recent problem has been dizzy spells i got them a few times throughout the year but its been very minor now i have been fainting here and there finally my doctors are getting me in for further testing and i feel a bit relieved but also still upset that it took so much just for me to be taken seriously if that makes sense. Other things have come on alot harder too I've always had issues with my joints, bones, muscles, and my legs specifically but its gotten almost unbearable some days i cant move without feeling like im decaying or collapsing in on myself some days my damn leg gives out and i end up bedridden till it decides to work again, however due to it not being that important to my doctor i guess im always just told to stretch, exercise more, or lose weight. The biggest issue has been the fact all of these, other then my joints or fevers, seem to come on separately if i have one ill usually hardly have another and its frustrating! sometimes i think im just faking it or im going mad i just want everything to be normal again i wanna go out on walks alone without the risk of hurting myself i just wanna feel better.

i doubt anyone read all that but if you did thanks i just needed to get this off my chest :)
if you are dealing with anything similar i hope you're doing well this shit sucks but you're not alone.
stay safe <3