I need help.

So I removed my micro sd card from my phone then inserted it again. I connected my phone with my netbook and deleted some files I did not need. I tried looking for my pictures but I couldn’t find them. I unplugged my phone and checked and none of the pictures were there. I don’t think I deleted them by accident. They were all on my phone just a few minutes before. I removed my sd card, restarted my phone, all that junk but the pictures still aren’t there. I don’t know what happened. The phone I have is a Sony Ericsson Xperia Play 4g. Does anyone know what is happening?