Can the sum of an infinite geometric series be negative?

I had a question on my calc exam today about finding the sum of the series ((-1^k)(4^(k-1))/(3^2k), where k went from 1 to infinity. I got the sum to be negative because the common ration was -1/4 due to the -1^n in the series. I was just wondering if it was possible for the sum to be negative? Thanks