Can Irregular Periods Cause Delay In Pregnancy?

I am 27 years old and three years ago i was 25 kilograms heavier and used to have irregular periods. Right then, after i have slimmed down to my current weight (55 kgs), I have noticed that I've been getting my periods every month like clockwork which would last between 3-4 days. I've been married for 9 months now, and my husband and I have been trying to conceive. I have a 28-day cycle, plus/minus 2 days, and I use an app to keep track of my ovulation, so we could always try for a baby when my ovulation window is open. My husband was never a drinker, but used to smoke quite a lot. I am very happy that he has quit smoking for two months now and we're both trying to live a healthy lifestyle.

So far, no good news. Two months after my husband has quit smoking, my HPTs are still coming back negative. Am I facing fertility issues here? Also, I think my periods are getting lighter and shorter and whenever that time of the month comes, I always suffer from very bad cramps. I would feel nauseated, my lower abdomen and lower back hurt so bad at times I thought I would pass out. We haven't really gone to see a doctor or an OB, as I don't know how to talk my husband into this without bruising his ego. I would like someone to explain things to me. Has my monthly period history anything to do with why I'm not getting pregnant? I need a doctor's advice and help. Thank you very much.