I see a lot of mention about various drugs (whether prescription medication or not) here. However little mention of food.
The fastest way into remission is a complete fast (24 hours), followed by a water fast, then a reintroduction of one macro nutrient at a time beginning with protein based foods. One of the biggest reasons for continued flare ups is stool in the bowels. Most UC sufferers are the large bowel, usually sigmoid and descending colon (unless you're unlucky). White fish only will produce little to no residue allowing you to eat without continuing to irritate the bowel. Fats are usually one of the biggest contributors.
I'd also highly recommend rectal foam based prednisone. It doesn't cause all the issues oral prednisone can cause and can bring about very fast relief if you're bleeding heavily. Who doesn't love something up their bum (all the Crohns and UC guys will know what I am talking about).
The purpose of the fasting method is 24 hours of relief (nil by mouth), rehydration, then a low residue diet aimed at giving your body what it immediately needs without loading the bowels back up. I usually do white fish for 3 days, then add a second protein like boiled chicken breast. I usually then add in white rice (as you've been eating) and honey. I do that for another days before adding in peeled white potato. If that causes no issues after another 7 days I'll add a fat, usually in the form of salmon. Still no fibre at that point. If all is good by day 21 you can start building back up the diet.
There are times when you may be an incredibly bad way and corticosteroids are a must, but usually the above will get you there in 72 hours.
I've had crohns (diagnosed) for the best part of 15 years now. I've been medication free since 2021 (if memory is serving me right) and not had a flare up in almost as long (touch wood).
On a tangent, theres some incredibly interesting research on cigarettes (have a google).
Anyway, I am personally very anti-medication at this point, primarily because mesalazine in particular has been responsible for most cases of CKD in Crohns / UC sufferers. I was never warned (and now know better to read the up medication before I take it) of the risks it poses. As someone else pointed out, as you go up the drug tree and get into the tier 4 meds which are very effective, the side effects also get infinitely worse.
I am labouring that point because if you can control it via diet you will save yourself a lot of issues down the road.
Anyway man, I really hope you are stable now and feeling a little less crappy. Its definitely no fun! Feel for you.