to young?

I'm 19 and my fiancé is 20. We live in a 2 bed 1 bath luxry apartment complex, both own brand new 2017 cars, both have stable jobs, we both make around 45,000 so about 90,000 together, we both have room to grow in our jobs. We have been together for 3 years! His parents are in there mid 50's and they keep telling us they want grandchildren. I think we are ready and have our family's support. But I just wanted some advice from young moms and what it's really like. To wait or to not wait? Everyone keeps telling me we'll never be ready no matter how much we prepare. Thoughts? We've actually been trying for over a year and haven't had any luck. I want to go to the doctor but afraid the doctor will not help because my age.