Trevor Siemian has had a pretty, pretty, pretty good last 12 months. He was drafted by the Denver Broncos despite throwing more interceptions than touchdowns in his senior season at Northwestern and suffering a torn ACL. He then made the Broncos after a strong preseason, made his NFL debut in a Week 15 game against the Steelers, won a Super Bowl and briefly became the only QB on the Broncos' roster when Denver chose to let Brock Osweiler sign with the Texans in March.
It's thus understandable that Trevor was feeling pretty good about himself.