Help me out with the hard pimples

Patient: I have thick stone like pimples over my face filled with lots of white pus.My Dermatologist recommended climiniskin cream but it didnt worked i have started using quadriderm rf which is effective but Dermatologist says to discontinue it(doc. says you will be having different colored patched skin after wards) .Shall i still use or discontinue it?Can the pimples be due to the reason that i squeezed my black marks with lot of pressure so there might be some blood clotting but how can it last for 2-3 years .My present age 19 years

Symptoms: White pus in the pimples and the size of the pimple is also big enough about 1 cm