Ash spoke Monday for the first time since coach Charlie Strong announced last week that the junior's career was over.
Ash figured he could be finished when he called a team doctor in the middle of the night after the North Texas game on Aug. 30 and said he was experiencing headaches and dizziness.
''The symptoms got worse the next day and the next day,'' Ash said. ''In the core of my heart of hearts, I knew I shouldn't be playing. I don't think my hopes were ever really high. I've met my quota for crying for the next 10 years.''
Ash suffered a concussion during the second week of the 2013 season in a game at BYU. That is the only concussion that Ash and the team have acknowledged. He returned two weeks later, against Kansas State, but left that game with what Texas officials called a head injury. He missed the rest of the season.
His second comeback lasted one game, the season opener against North Texas on Aug. 30. Ash said he figured the end was inevitable after seven or eight days of headaches following that game. Though he was tackled several times in the game, Ash said, ''I didn't take a vicious blow.''
Strong waited a few weeks for Ash to arrive at a decision that was not really his to make. When Strong announced last Wednesday that Ash would no longer play, the coach said he told his quarterback ''there was no way we were going to let you back on the field.''
Even so, Ash said he appreciated that Strong, and the university, allowed him the time for contemplation.
''The doctors and coaches, they all pretty much knew I wasn't going to be able to play,'' Ash said. ''But they never told me that because I think they knew if they just took it away like that, it would have jolted me. So we went through due process and helped me understand why.''
Ash, deeply religious, said he ''prayed a lot'' while considering his future. He is concerned that future might include lingering effects from the injuries.
''That obviously played a role'' in his decision, Ash said. ''I've felt better the last few days. There are still things once in a while that are a little irregular.''
Ash was 15-7 as the Longhorns' starting quarterback. He had some big moments, leading the team to a 75-yard game-winning drive at Oklahoma State in 2012, and a comeback victory against Oregon State in the Alamo Bowl that season.
But he failed to beat rival Oklahoma in two tries, both blowout defeats. He was benched at Kansas in 2012 and watched from the sideline as Case McCoy led Texas to a narrow victory. Ash wishes his health would have afforded him the opportunity to leave behind a stronger legacy, to reach some goals.
But, he said, ''I'm at peace.''