Yes it is perfectly normal. my two sisters are both single mums and they do find it difficult to be the mother and father. it may not be him who is missing something in his life it may be you. the best way to be a mother is to be there for your son as he grows up. just do the best you can for him. there is loads of women in the world who feel not good enough or as if they are not good enough. maybe have some pamper time to urself when he is asleep. or get a babysitter and go out with friends. try and go to clubs as well for children i.e. swimming clubs, music clubs, this will help you meet lots of women in ur situation so youll make friends. your son will start making friends too as time goes on. hope this helps you