What does it mean when you've been with a girl for a few months and she suddenly starts ignoring you?

Was seeing a girl for a few months, we were both incredibly busy so we both decided to slow things down a little bit, but then we decided to remain mates because we were just too busy(we're in college)..she just ignores all my texts now, I understand that some girls do that if their not interested anymore, but is there some form of twisted mind game that some girls try to play when doing it, does it always mean they dont want to talk to you again. Because to be fair, we never argued and I didn't actually do anything wrong : / it was about 3-4 weeks ago I sent her a card and a box of chocolates because she sounded pretty stressed on the phone and wanted to cheer her up, she seemed happy when she received them, but recently found out she was freaked out by them, and found it abit weird... Since then, shes been alil funny with me, really thought it was the best thing to do, something thoughtful and alil different, but clearly not...