Pushed to Accutane after 1 month of tretinoin

My dermatologist wasn't quite happy with my results and also said my antibiotics i.e. Minocycline isn't walking anymore. So she told me to take Accutane of 20mg daily for 3 months.

I am using Tretinoin cream of 0.025%, it has really worked on my natural glow but gave moderate closed comedones on my face.

I have heard Tretinoin takes 12 weeks to show its results so I don't know why my dermatologist prescribed me Isotretinoin. Should I tell her to wait another 8 weeks ?

Please comment down your suggestions.