His frustration was mild, and not at all directed toward Cecilia in any kind of way that could be construed as angry. But he knew she was stubborn, and she knew she would sacrifice her own well being if she felt people might need her. It was admirable, but also, yes, exasperating. At some point, he wanted her to put herself first, but only for her sake, but for everyone else's. Owen was more concerned about people in this place becoming vulnerable in any capacity, especially physically.
"I get that," Owen said gently, because he did. Nobody wanted to put their guard down in this place, especially now. Himself included. "But you can't let your health suffer. That won't help anyone." He reached out to touch her hand, sliding his thumb over her knuckles. "I know I couldn't do shit for you the other day. But I'd make damn sure nothing happened to you here. No one would come within ten feet of your door without me knowing about it."