I had a C-section a month ago and I went to my obgyn he said it all good but it still hurts and it burns a little, can I workout or have sex?

Varies. Dr dimino's advice is typical wisdom, but some recent studies have suggested that it is safe to resume physical activity much sooner than has been traditionally recommended. A study by minig et al showed that the pressures exerted on the incision doing typically activities like getting up from a seated position exceed what one would have doing moderate lifting or exercise.
Post Csection limits. After a c-section, hold off on sex, vigorous exercise, and heavy lifting until 6 weeks after the baby was born. You can start light exercise, such as walking, as soon as you feel comfortable. After the 6 weeks and your doctor's approval, work up to vigorous exercise slowly. If it still hurts, wait longer. Some women are able to do it at 6 weeks, but some not until 12 weeks.