First did you buy that from lovehoney.co.uk or .com?
Well if the charging lights on, put your hand on the plug and toy to see if it hot and smell it, if theres no hot heat or burning smell then all clear!
let it charge for 15min, then try using the toy unplugged?
of course a toothbrush uses good amout of power because of the motor, so if the We-vibe 3 has moving part, and it goes ok. then the toothbush charge might be suitable if the amps are right and volts too, but for some reason it breaks you "may" or will have no come back on the toy!
If the toy was brought on the UK lovehoney website contact them first, you may return and get a proper uk one for FREE!