Photos disappeared - please help

I was deleting photos from my phone DCIM through my laptop (Windows Vista). I specifically selected about 900 photos that I wanted to deleted. For some reason my current folder, that wasn't selected, also disappeared and now I'm left with just my oldest photos. I've lost all the photos from my trip around New Zealand, so this is pretty upsetting. The photos aren't backed up on iCloud, but they have to still exist somewhere, right? Help much appreciated.