Pcos is a bitch

I've been trying to get pregnant since July. But this is my second go round. Me and my boyfriend tried for 3 years straight and I didn't get pregnant so I got to tired of trying and got back on birth. I got off in July and it's just been a up and down rollercoaster. It seemed like I was pregnant back in August. But unfortunately I wasn't. I use to be on Letrozole years ago and want to go back on another fertility pill to try again. I'm just really trying to make this happen now. I already have a 10 year old son. My kids are going to be so far apart in age. I just really don't know what to do anymore.