Am I doing enough

Hi guys

I need some advise on how many workouts I should be doing each week. I'm pretty active at the moment due to my daily commute to & from work. I walk over just over 1.5km to my train then cycle just over 4km when I get off the train to my job. I repeat this on my way home. So in total I'm walking about 15km & cycling 40km a week all at a pretty good pace.

I'm not home as early as I used to be so doing a 35-40 min work outs is not really an option. However I do need to do more upper body & core. So what I was thinking is if I do a FB 15 min upper body with dumbells x 1 day, then 20 min core x 1 day & a long whole body work out at the weekend, would this be enough along with my daily commute to help me tone up?

I'm also doing an overhaul of my diet at the moment as I have a tendency to either eat too little one day & possibly too much another day so I'm trying to change this too.

Any advise greatly appreciated :-)