I was diagnosed with UC at age 19 and finally had to have the J-Pouch surgery at age 26. I had a two step surgery, removal/ileostomy/heal, then take down. I had an ileostomy for 4 months - like you I was young and active - I personally hated it for a number of reasons; uncontrollable noises, ballooning, leaks, odor, burning, skin problems, trouble being able to change out bag by myself, uncomfortable overall for me, not to mention the relationship issues. I had the take down and it does take time to completely heal, you do have a lot of BM's the first few years, probably won't sleep through the night for a while as well. Also, J-Pouches can be noisy too, but for me not as bad as the ileostomy, sounds like hunger pains more than gas sounds. You may have pouchitis too, which feels like UC. Remember, everything takes time to heal and your body needs time to adjust to something totally new.
While I had my ileostomy my surgeon recommended exercising those anal muscles a lot and I did (squeeze/release). They can weaken when not being used when you have your ileostomy and are very hard to build back up. I did these all day long with my ileostomy and I never had one accident overnight or during the day (and I have had 2 children since then) up until I was given remicade 20 years later (I'm one of those patients that also had Crohns in my small intestine and we didn't find out until after surgery in the pathology tests. On Remicade, I was trying to heal fistulas which is common with patients with our diagnosis - didn't work for me). I was also told to try and hold BM's as long as possible in the beginning to start stretching the pouch. I would always hold it as long as possible those first years to help slow down BM's - for me it worked, it can be a little painful, but worth it. I do struggle with pouchitis at times, but as I have gotten older I have had less pouchitis but I deal with the fistulas. In the beginning I also figured out if I didn't eat after 6 pm, I could sleep through the night.
My negatives of this surgery is maintaining a healthy immune system. When I get a flu, cold, sore throat, etc., I can have it for weeks. Also, maintaining levels of important nutrients and vitamins; iron, calcium, and the side affects that when lacking these nutrients can give you; thinning hair, brittle bones, decrease eyesight, etc.
I haven't been on any prescription drugs in years and if a bad bout of pouchitis hits me now, 2 Aleve is all it takes to get me back on my feet - I have had my pouch for 27 years. Be careful when taking prescribed drugs for pouchitis, they do have long term side affects, which I have dealt with (tendons, muscle, eye sight, numbness issues). Take only what you need to get better and get off of them. Don't become dependent on them thinking you can't get through a day without them. Give your body lots of time to adjust and take one day at a time. Living with the pouch will get better - perfect? No, but better than life with UC.
I eat what I want and have never had a problem with fruits, veggies, salads, etc. I am an active 54 year old woman with a regular exercise routine, a healthy diet, except on weekends 
, do plenty of activities camping/hiking, golfing, bowling. As I am now dealing with menopause, which I find is way harder than dealing with my pouch, my goal in life is just to keep moving
Personally, I love my J-Pouch way better than the ileostomy. It has given me a more normal life and I am so grateful for everyday, even if it's a bad day.
Good luck to you🙏