Lets look at your options, if your plan is to raise fold, then a 2.7x raise on the button with blinds raising next hand would put you at 10BB effectively which is clearly danger zone. If your plan is to raise call then Im in the school of thought that its better to just get it all in. Whether it is perceived as weak or strong it still puts your opponent at a difficult decision, because no matter what YOU are seeing the river. With 15 BB AT suited is a fine hand to rest your fate on, It just so happen that he had the goods, it happens, I see no mistake here.