Constipation Problem

After Eating a Meal I feel like passing Gas, But after certain difficulty i pass it, but still feel like my Stomach is filled with some sort of Gas, Try to pass Stool, but with difficulty pass little.
Due to this i fear to intake food hoping it might still worsen as the stool amount might get increased in Intenstine
The Doctor had sugested to take Cremalax Tablet in Night, but i took it in Morning hoping i might pass Stool in morning As i could not i opted for the Tablet But still passing Stool was difficult
Along with this i was given a capsul for Smoothning the Muscle
But still nothing is working. Please let me know What to do, Is this the common problem and will be for life time
With this symptom can a take Food regularly