Is my salmon bad?

I bought some marked down salmon yesterday and the best by date is today. I opened the package (vacuum sealed, i believe it comes to the store frozen) and immediately was hit by a very strong fishy smell. it doesn't feel slimy or have an off color or anything, just smells very strong. I cook salmon a lot but have never bought a vacuum sealed loin, so I wasn't sure if it was just the packaging. I'm a bit nervous to eat it now, what should i do?