Though I coach adults with ADHD, many have never received a formal diagnosis. 

Here are just some of the many common adult ADHD characteristics: 

Inconsistent Attention  Sometimes extremely focused, other times no attention to detail; stopping projects when they’re 80% completed; forgetfulness with dates or events

Impulsivity interrupting others in conversation, making very quick decisions about important things

Sensitivity especially vulnerable to criticism, sometimes perceiving self as a failure; can lead to perfectionism as well as procrastination.  (See also information about RSD, Rejection Sensitive Dysphoria)

Time management difficulties succumbing to that mysterious 30-45 minute vortex of lost time between putting on shoes and actually leaving the driveway; being late, misjudging how long tasks take