iphone keeps telling me to connect to itunes.. HELP!

My iphone has recently been playing up lately and has affected my apps. So usually you would restart your phone so i did. Then it kept its apple logo for about 30-45 minutes?! So i decided to reboot it again and was like that for a while. Then screen went black, so i restarted it and afterwards it's telling me to connect to itunes? I did it, but it didn't detect my iphone? So basically my phone is now locked with it telling me to connect to itunes which won't work?! HELP ):