Why isn't it happening.

My husband and I have been trying for 18 months for our 2nd baby. We had a chemical pregnancy last year but nothing since then. My doctor won't test me so my husband is getting tested. I didn't fair too well after the birth of my son so I think something could have gone wrong there although I have been assured that my issue from birth will not stop me getting pregnant again. Just over trying and wish we could get pregnant. So lucky to have our little boy but still feel a hole for this little person we don't have yet.