Sour taste in secondary

[jpeebs]

Hey guys. Doing a cherry wheat using a brewer's best weizenbier and 3 pounds of cherry purée. Brew day went well. OG and FG were right where they needed to be. Took a sample today to see if alcohol content had changed at all and took a taste. Could've been cause it was warm and flat, but it seemed to have a sour taste to it. Should I be worried? Or let it ride?

 

[jpeebs]

Pretty beautiful if ya ask me. On a side note, is it necessary to use a carboy as a secondary? All I have is buckets...first time using a secondary.