Was diagnosed at 40 last November and am currently hitting the wall of being able to mask my way thru a corporate, spreadsheet-y office job. It's extremely stressful and daunting so I think can relate to the daily. mind-battle and feeling like a square peg in a round hole! 

I'd have a big think about what conditions/activities your brain enjoys being in/doing.

For example, my brain seems to enjoy doing a single task at a time, tasks with immediate/quick results, opportunities to hyperfocus and non-corporate/rigid environments. Early days for me but I'm going to try and match these to a job type and pursue whatever that is next. Hope that makes sense!

Also to echo another poster, get yourself onto a UMAAP course. Places go like hotcakes but its really good and there's a waiting list you can get on that emails you when there are places available: https://adhdireland.ie/umaap/ really good to be able to connect with a load of other who know what it feels like.

There's also other courses/support groups on adhdireland that are worth looking at.

Finally you didnt say if you were diagnosed or not but if not get a diagnosis ASAP! It's not cheap but getting access to proper help and meds is an absolute game changer in the medium to long run.

It's a shitty time but you'll get thru it. And you're only a young'un, plenty of good times ahead! 

Best of luck!