Hi
This is a nasty disease that is with you for life. And Flagyl is a nasty antibiotic with severe side effects. So what you are experiencing is probably a combination of side effects and infection. I'm sorry to say it takes 4 - 6 weeks to get over an attack and start to feel better, and the more attacks you have, the longer it can take.
You are right in thinking the doctors are pretty useless. The problem is there is not one simple solution - everyone is different and has to find out what triggers their flare ups. Although the common thought now is it is not diet related, that is not strictly true. Most of us on this forum have discovered there are certain foods each of us cannot eat. For me it is gluten/wheat and full fat. For others it might be dairy, red meat, popcorn, seeds, skins. In fact all sorts in various combinations. We identify these by keeping a food diary and noting down if anything seems to make us feel worse over the next 48 hours. One recent post from a sufferer who was feeling much better after a few weeks, reported she had tried to introduce back a food and suffered a setback. Another trigger, not food related, is stress which as a single working mum, you will undoubtedly be suffering. The 3rd component is genetic, but you didn't get to pick your birth parents!!!
To deal with a flare up: At the first sign, immediately go on a fluid only regime for at least 48 hours. That gives the bowels a rest and hopefully stops it. But once you are given medication, you should follow a fluid only diet as well - broth, jello, water. As you start to feel a bit better, you can introduce low residue foods like mash, steamed fish, grilled chicken, yogurt, white bread. Then slowly reintroduce SOLUBLE fiber back into your diet. GOOGLE will advise you. One poster found All Bran too harsh and instead has bran flakes. I have proper porridge (not the pre-packaged dust). I make a lot of home made soup which I freeze in batches so it is quick and easy to re-heat (and cheap). I also have veggie purees like carrot/swede/parsnip/celeriac/potato in various combinations. The meals should be small, well cooked and chewed thoroughly. The final stage is to try and introduce back other foods and note the effect. I would also advise you take a daily stool softener like Metamucil, which will help clear out your system daily and prevent a build up of matter in the pockets which can become infected. Also a good probiotic to replace the good bacteria which will have been wiped out by the Flagyl.
It is a lifestyle change. I was diagnosed almost 17 years ago and live a normal life. I worked (missed only 3 days for hospital appointments/tests), played competitive sport, walked and gardened. During that time I had 3 flares in the first 14 years. When first diagnosed it can be hard to tell the difference between a flare up and the pain of inflammation during the healing process, hence the advice to have a 2 day fluid regime. If it doesn't go away, it's a flare up!
This is just a brief overview of my experiences. You will find loads of helpful and informative posts on this forum from people who are going through exactly the same as you - you are not alone. Also lots of tips on how to manage your diet and this disease. Best wishes.