Dez Bryant -- I'm Not Selfish ... Just Trying to Get Paid!!

Dez Bryant says he's sick and tired of people calling him "selfish" for holding out of Dallas Cowboys training camp -- saying he just wants to be paid fairly and he's been quiet for too long.
Long story short ... Bryant and the Cowboys are in a heated contract dispute -- with Dez needing to strike a long-term deal by July 15th or else he'll be locked into the league-mandated franchise tag salary for the season ... which is roughly $13 million.
Dez has remained silent on the issue ... until now ... when he went to Twitter and wrote, "Everybody voicing opinions..13 mil is cool but Where is my security? I'll wait ...5 years without complaining..So how am I selfish? #family1"