Surface Pro 11 Battery Issues?

Its been less than one year on my surface pro 11 and i was feeling like the battery was not lasting as long as stated and also lagging at some points. When I did the battery health check it showed that it had dropped around 13% from design capacity. Is this normal and should I get it repaired/replaced under warranty? Its just bit of a hassle as I am outside of the US.... 

Microsoft surface pro users outside of the US doesnt seem to have the proper support also, no contact and no email response from raising tickets....