My xperia m2 has switched off wont switch on and wont charge

To see if it's simply stuck, hold Power and Volume Up for about 10 seconds, if nothing happens, it's completely out of juice.

If you haven't already tried a different USB charger than the one you've been trying, try a different one. I've had a charger or two die on me, causing me to panic, thinking my phone was unable to charge.

Aside from that, if nothing works, it sounds like your phone will need to go into the shop for maintenance.

Best of luck!