Am i losing calories/fats?

i used to be in the school badminton team and we're always made to go through rigorous physical trainings 5times a week. i've already stepped down from badminton due to GCE OLevels examination but still play/do sports like badminton, roller blading and running almost every single day for about 45mins. however i do not feel any fatigue while having fun but i always usually end up perspiring alot and i don't feel my heart throbbing very hard. so i'm wondering, am i losing fats/calories?