Fertility problems?

My husband and I have been trying for a baby for almost 6 months now. I’m 23 and have had one successful pregnancy, my son is now 2. My cycles used to be pretty long but the last 3 months they have been about 25 days long. I do get my periods and pms symptoms but I’m not sure if I’m ovulating? My husband is 31 with no children or previous pregnancies so is it possible he has a low sperm count or something?

How long does it normally take to get pregnant? With my first pregnancy it was the first time so I guess I don’t have much ttc experience.

I’m worried I won’t be able to get pregnant again or something..