I can relate, I became unwell at the age of 16 with diseases that just spiralled upon themselves.
Some backstory, I originally got diagnosed with lymphocytic enteritis, an untreatable form of microscopic IBD, this then caused me to become intolerant towards 8 different types of sugars. After almost a year of misdiagnosis I had developed Chronic Fatigue Syndrome, which has a lower QoL score than most mental disorders including depression and a lower QoL score than colon cancer, with a low chance of complete recovery and takes around 6 years of strict therapy and life management. Further on I developed GERD, Hyperthyroidism, Chronic sleep deprivation, Chronic dehydration, B12 defiency, Insomnia, Tendonitis of the knee and a complex cyst in my primary hands joint.
I did not take one pain killer or pharmaceutical besides vitamins. I approached the battle far differently, pain is all in the mind as goes the saying, if you are capable of winning the mental battle then you’ll always end up on top, no matter the obstacle, it might not cure the issue, but sure does help. I also approached a variety of pseudo medicines.
Past all of this I ended up completing a degree in psychology, due to my developed passion of the mind from using it as a tool to battle illness.
My functionality a year in was 6 hours awake a day, less than one out of bed for an entire year. Whilst needing the toilet for violent diarrhea over 15 times a day, with chronic bone and muscle pain while also suffering a variety of neurological problems such as severe memory problems.
As soon as I understood how unwell I was I started specific self reinforcing notions. Simple things, no matter how bad the day was I would tell myself I am going to get better, I am going to make a good future for myself, the weather is nice, etc. I would read as often as I was feeling capable, read anything, learn something, watch something. One of the worst things you can do is tell yourself how much you hate everything and only occupy your time with thinking about how bad everything is.
Besides the mental game, there are some key aspects to take on when navigating the medical system. If you want something you demand it, specialists should be your go to. MRI will almost always guarantee results, though rather costly. Ask the doctors about alternate options, tell them how you feel and don’t let them condescend you. Pseudomedicine can be good, just research that it isn’t entirely harmful or a scam before hand. If time is of the essence the consider private health.
I am lucky to have such doctors, I went to a VPRS rehabilitation clinic which helped my CFS and life in general. My endocrinologist was very helpful with managing my thyroid problem , however the IBD I have was untreatable and incurable, thus I seeked pseudo medicine and now get Diarrhea less than once a day.
Essentially your approach should be maintaining a healthy mental attitude, if not in yourself, seek a psychologist ASAP. Lots of doctors have no idea and you should be assertive and questioning rather than just being a yes person. Pharmaceuticals are ideological a trap because they aren’t made to cure, only treat the symptoms, seek healthier methods where possible. Don’t internet diagnose yourself, however do question your doctor on your queries. If you aren’t getting proper treatment request a specialist/ a new one. Pseudo medicines can partially help.
If you really feel like you’re dying, hospitalise yourself, go to ER and explain your symptoms, they get quick results.
If you have time seek a psychologist, they help even if you don’t have a mental problem
I had a whole paediatric team working on me when I was in the age category from the royal children’s hospital of Melbourne. Then a new team of specialists upon adult hood. At a rough estimate I had 5 specialists and a GP I had to see regularly, so probably since the start I have been to see a doctor at least 150 times in 4 going on 5 years and still countibg. Get used to it if you wish to get better, which you should, because giving up does not do anyone good.
EDIT; about your Crohns, it has a simple inflammatory marker test and almost always shows in a complete colonoscopy + gastroscopy. The symptoms for many are the same as colitis, however people often to get eye problems and a few other token symptoms.