Did you try contacting the airline for details

Here a link with some information.

http://www.qatarairways.com/global/en/baggage.html

also could get contact info here

http://www.qatarairways.com/global/en/offices/contactus_philippines.html

In addition as they say in their site

"Excess baggage will be subject to additional fees, to be collected at the airport. For excess baggage rates please contact your nearest Qatar Airways Office."

Regards!!