So i went on holiday for 3 weeks when I came home I noticed my trip computer was reset to 0 miles... pretty sure I didn't reset it before I went away... I never do... it was weird. I also noticed when turning the car on for the first time it was like reallly rough to drive like the battery had been disconnected kinda tihing.. it I assumed this was to be expected as normally the car was driven daily for 30miles at least and to go from that to nothing for 3 weeks I figured this was normal..

but even now a few days on after driving it, the main thing I see wrong is that when I first start the car, even after its got a warmed up engine, it seems to struggle to start... normally when i first turn the key, the dashboard will stay lit up e.t.c it wont show details but the lights stay on.. and all the meters in the car will go to their correct places right from the start. Now however... the dash board will flicker quite badly... and the starter motor sounds really slow... all the meters will go up a bit at the start and then back to zero or will jsut freeze on the way up for awhile even after the engine is actually started... then it will correct itself after like a 2second delay...

does this sound like a battery on its way out? or is it something else?

I'd get the alternator checked out. If not that it could be the battery.

Get the battery checked my dials went a touch slow when my battery was on its way out, take it somewhere they will check both the alternator and battery, probably just the battery if the battery light isn't on while running.