“his hands became feeble.” This is an idiom for him being discouraged and dismayed and as a result not really knowing what to do.
“troubled.” The Hebrew verb is bahal (#0926 בּהל), and it means to be disturbed, dismayed, anxious, or even terrified. It is hard to pick a single word in the translation, because different people would have had different emotions. Some people would have been just disturbed, others dismayed, and others anxious, and many would have had different emotions at different times. In any case, the people were troubled at the death of Abner, one of the pillars of the kingdom.