What should I do if id two rounds of Accutane and my acne is just as bad as before? I know efficacy dec each time so is a 3rd course going to help?

Inadequate treatment. If your acne truly is "just as bad" after 2 courses, that's a very unusual situation; i've never seen it in 30+ years of prescribing accutane. Your dosage or duration of treatment may have been inadequate. With slow responders i add an antibiotic, usually ampicillin, to speed things up. You might try seeing a dermatologist with more Accutane experience, or one equipped to do levulan treatments.
SEVERE ACNE. You must be under the care of a dermatologist as Accutane has several side effects. It can affect your blood, liver, increase lipid levels, dry eyes and mucous membranes, back and joint stiffness, depression and suicide. So if not helping why risk the above problems? Treatment last 16 to 20 weeks.