When did you know you were ready for baby #2?

My son is currently 13 months old and my husband and I have been talking about TTC #2. We always hoped to have our children 2 years apart, but I really don’t know if I am ready to start trying. Some days I feel like I’m ready and other days I worry about if I’m ready for 2. How did you know you were ready for another baby? How was the tranosition from 1 to 2?