my iphone locked after ios 8.1 instalation

Need help

My Iphone 4s locked after upgrading to ios 8.1.

In activation my apple ID and password do not accepted.

I have no success retrieve my old password from my apple id site.

I think iphone locked.

The only thing I can see on the activate phone screen is the following:

This iPhoneis currently linked to an Apple ID (xxxxx@gmail.com). Sign in with the Apple ID that was used to set up this iPhone.

Is there any way to retrive old password or unlock my iphone ?

How can contract to iphone support to be solve this problem?

M.B.