I've gotten this exact order of messages before when involved in a battle, and this is how I see it:
At 11 a.m., you were ahead - maybe slightly, maybe more.
Sometime between the 5 p.m. and 8 p.m. cycles, your "battle opponent" put in enough effort to put you slightly behind. That's why you got that message at 8 p.m. (you'd have gotten it earlier if he'd put the effort in during a previous cycle).
If you don't (or can't) put in any more effort, you should expect to lose this battle - I've never won a battle when I got this message unless I put in more effort and got another message indicating the situation had changed to where I was ahead again.