How long is normal if I have not been activatly tracking / trying to get pregnant?

I am 28 years old and have wanted to get pregnant for years now. Me and my partner have not used contraception for around 3 years however we dont have sex often enough maybe every 6 weeks or so but maybe a lot of times across a few days like a binge and then a drought for a while (life is busy!) we have only started looking into <a href="https://play.google.com/store/apps/details?id=com.glow.android">tracking ovulation</a> etc and actually doing it at the right time. Is this normal that we haven't been successful taking the casual approach? Do we really need to be trying as in checking when Im ovulating and doing it then every month until it happens? Also when I was 21 I had a surgical abortion could this affect my conception now? I have regular easy enough periods not really bad cramps but I do get very moody!