First of all, thank you a lot guys. That is an interesting thoughts, Pitysister, I will surely try to read the things you have mentioned.

Even squats with 60kg is too much for my lower back, so i definetely need to work on squats, but not sure about deadlifts, i don't want to cripple myself, but i will consult with the trainer.

Regarding the calories counting i am pretty much clueless, could you give me some tips how to calculate these?

Many thanks for the replies, hopefully there will be more