Mario, you have plenty of time to train for your next marathon in May. It has been 3 weeks since your marathon so if you are feeling fine think about slowly increasing your training before starting a training schedule early next year. Do you have a schedule in mind? You could start by looking at the schedules on this website under training.
With regard to running two marathons in September and November, there is not much time for resting between and prehaps someone with more experience than me could advise you about training for those.
Do you run half marathons and 10ks in your build up to marathons?