I agree with Hope4best. With a regular cycle, and a having already had a baby, you're probably ovulating and should be able to get pregnant. Both 28 and 32 days are within the normal range. However, OPKs (ovulation predictor kits) can help you pinpoint when you're ovulating so you can better time when to have intercourse. Good luck!
You should be able to get pregnant. Do you know if you are ovulating? They have ovulation kits that you can use to find out. If you are ovulating then continue to try for next 6 months and if no luck talk to your doctor. Good luck!