GAD develops slowly. It often starts during the time between childhood and middle age. Symptoms may get better or worse at different times, and often are worse during times of stress.
People with GAD may visit a doctor many times before they find out they have this disorder. They ask their doctors to help them with the signs of GAD, such as headaches or trouble falling asleep, but don't always get the help they need right away. It may take doctors some time to be sure that a person has GAD instead of something else.
This answer is based on source information from the National Institute of Mental Health.