Is it bad decision to train more than once a day?

No. Many high level athletes do this to achieve a greater overall training volume (for example elite runners and triathletes, nfl pre-season workouts, intercollegiate rowers preparing for spring racing season, etc). As long as you are not overtraining this is a good way to fit exercise into a busy schedule-for example you could do am cardio/aerobic workout and pm strength/cross train or yoga, etc.