Tri hard ...well trying at least

Got up 'early' for a Saturday for me anyway and went to the gym and did  some spinning, cross trainer work, boxing(only a little vs the bag unfortunately) then swam for a bit, felt a bit better on the front crawl. Then home and out for a busking festival and unfortunately lots of booze. Woke today with a hangover but eventually went for a bike ride about 15k I think . Need to get more time on the bike as have the 24k plus the 4k run at the next event . Legs and knees in particular are in bits at the min so might give shouty man a rest and swim every morning next week depending in the time LLLneeds  to get out.  Are there occasional tri goals (sprint ones lets face it ) enough to stretch myself, or should I leave it at that considering my body complains a lot... I am sore almost every other day and my fitness, although good,is not dramatically improving? Do we all plateau or should we just do the right thing for our bodies (which in my case is eat less and do yoga every day for a fiery gal like me). Any tips, let me know. Mind you, although I might  find an inner calm, would I miss the high octane bit which comes with pushing your physical limits to do something you have not tried before.  Or is this an itty bitty mid lifer for me?