Bad DVD or cheap DVD player or both?

I have recently been having trouble with my DVD player. It is relatively new (only two months old; only exposed to 10 DVDs). I put in a multi-layer DVD the night before last and it played fine. I tried another section last night and it freaked out. Various screens froze. It skipped. It went to a black screen. And I had to unplug it and plug it back in, in order to get the DVD back out. I tried another DVD in it, which played much better, though less than perfect. Then I tried two more, which would neither play nor eject. WTF?