How long after coming off the pill did it take for you to get pregnant

I’m 25 I had my daughter 29/4/17 and soon as I came of the pill I got pregnant with her in my first cycle off the pill, when she was born I went back on to the same pill 6-7 months after have been on the pill for well over a year and now I came back off the pill in October 2018 and I still have not gotten pregnant, I have been using opk’s I just feel like giving up, I just keep thinking it’s just never going to happen, I am a only child and I don’t want my daughter to be an only child I want her to have another brother or sister to grow up with but I have so much doubt that it’s going to happen and now some of my friends have gotten pregnant with out even trying they were scared to tell me because they knew we weren’t having any luck, why is it so hard this time round it breaks my heart every month, I’ve gone to my doctors they told me to come back if it’s been a year and still no luck, is there anything that can help my chance of getting pregnant???