I’m sorry you feel alone and scared, it is worrying when our bodies throw up these things which may or may not have causes linked to neuro disorders!
I don’t have advice as such but can relate to some of what you mention. I visited my GP last year having developed altered sensations in my right arm, hand and foot which had been constant for 3 weeks at the time. Just prior to this I had been clumsy, dizzy and sometimes breathless at work which was in a kitchen in hot weather.
My GP ordered various bloods all of which came back normal and then referred me to Neuro.
Fast forward to this summer and I kept tripping on my right foot which I put down to not being good at walking in flip flops, for a week or two. I also noticed my weeing was very stop/start and taking more effort.
Suddenly one mid morning I hadn’t been to the loo since 9 the night before and went into A&E where they catheterized me after checking for infection etc. Sent me home on TWOC (trial without catheter) ie keep it in for 5 days then have it out to see if bladder function restored.
3 days later couldn’t balance or use right leg at all so back to A&E where I was admitted and given 2 MRI scans and a lumbar puncture, plus 3 days IV steroids.
Symptoms improved almost immediately!
My advice would be to think about any symptoms that may have a neurological cause and write them down in a timeline, how long they lasted, whether they have recurred etc. As you’re only 30 you don’t need to think back quite as far as me as I have a good 20 years on you…but I included as much as I could remember.
ie. - random short lived numbness/tingling; numerous vertigo episodes for a couple of days; burning ankles for a week or two; and so on.
Neuro (assuming this appt stems from the bladder retention??) will certainly appreciate as much orderly information as you can give and may do some simple reflex tests etc and refer for scans.
It may or may not comfort you to know that I was diagnosed recently with RRMS - but that I have probably had it for decades according to my Neuro. This means I have had 30 odd years of very mild if sometimes annoying symptoms which have only just started to have any real impact on me. I guess all this tells you is that * IF * MS is eventually diagnosed, you could very possibly still have years and years of little impact on you.
Please do let us know how you get on and maybe one of the other lovely folk on here can offer more advice