Probably a dumb question, but have you tried reinstalling and/or disabling any plug-ins you might use? Im also using Chrome and have no problems with G-mail and the back button :/
I pretty much explains everything in the video. I hate having to explains things like this but writing as I never seem illustrate my problem correctly.
So yeah, watch the video and let me know if you have a possible fix :) I can pay you like 5 dorrah or something if you have moneybooker :P...