I have an unopened can of anchovies. The top & bottom surfaces of the can look "bowed out" and a little dented, and pop a little when I press on it, as if air had got in. I first noticed a little oil on my fingers after taking the can off the shelf. Other canned fish in my pantry don't have these qualities--no dents, no bowing, no popping. Should I toss? Label is Cento brand, "semi-preserved", packed in olive oil and salt.