Trying to get pregnant

So a little back story I’ve gotten pregnant before but had a miscarriage after that I have not been able to get pregnant again I’ve always had irregular periods since I was 14 we don’t use protection but I still haven’t gotten pregnant it’s been 3 years since I had the miscarriage I’m starting to get worried that I can’t even get pregnant anymore I also get really stressful at times when I don’t even have a reason to be I just wanna know if anyone has experience this and what did you do to help you conceive and get pregnant please