Almost 35 and TTC #1

My husband and I have been TTC for 3 mos is on my mind morning, noon and night. Am I too old? Did I wait too long? I've always been so safe and so naturally I thought I would be pregnant immediately. Just when I started getting a tiny bit discouraged, I found this app with tons of inspiration and people going through the same thing as me! So tell me...when should I go to the doc and get checked out? Ahhhhh!