Is it normal not to bleed after curettage and whether it indicates some complications caused curettage as cervical stenosis or asherman's syndrome?

Period : While some people may have bleeding spotting in the first few days after surgery it's not necessary to do so. Some bleeding would be perfectly normal but a lack of bleeding would be even better. What you're looking for this for a return of your normal menstrual cycle during the following month.

Not normal: There should be bleeding immediately after you had curettage. After days of curettage bleeding should be stopped. Curettage can cause Asherman syndrome and stenosis but it is clinical diagnosis after many days after curettage which cause infertility and chronic pelvic pain.