mobile

I am using CM12 nightlies on my N900W8, and I haven't had any problems until I tried to flash a new nightly (while running 20150410-NIGHTLY-hltetmo) and instead of booting into recovery I got a black screen. After taking the battery out and back in and trying again, the same thing happened. When I started it back up again the internal memory was completely wiped, I have no idea how or why. It can boot into download mode but I cannot get into recovery and therefore can't flash a new ROM or recovery to fix it. What do I do?