From what you've posted you have reason to be concerned imo. The one that went off like air raid sirens was when you came home unexpectedly from work to find him locked in his bedroom with another female. I don't think that you should have to call home to give advanced warning that you'll be there when you're not expected.

I've had many male friends through the years, I cannot think of a single situation that another male and I were locked in my bedroom. Even when I was extremely ill and a good friend came to check on me. All my kids were home as was my husband, but friend just said he'd come back when I was able to go downstairs.