Yes, he regrets having accepted that deal. Having powers is not as good as he thought, especially because of what it did to his sister, Lisa. And damn, Leonard misses his cold gun.
He's trying to be a good boyfriend and keep you completely away from all news about him. —He has always kept you away from the criminal life, but this was a little different.—
And even though he thought he could handle that secret, lies have short legs.
Leonard had accidentally become distracted while watching one of those stupid hockey games, it was so stressful that he didn't realize that when he hit the coffee table in frustration, his powers betrayed him, causing his hands to stick to the table frozen.
And to top it off? You returned to the apartment.
"Yeah, uhh.. Hey there, hon." He looked at you nervously, thinking of what excuse to tell you.