my boyfriends complex allows me to stay there 14 consecutive days . if I leave on the 13th day and come back 2 days later does the 14 days start over

Well, that’s certainly possible, but I would think they’ve encountered that loophole before you.  My point being that I’d be willing to guess they’ve tied up that loose end in the lease or in the rules and regulations that connect to the lease.  To get to the direct answer, you’ll need to look to the lease and then to whatever rules or regulations the complex has in their entirety (and how they are connected to the lease).  If you’re uncomfortable doing this alone, you might find it helpful spend a few bucks for an attorney to research it and give you your answer.