Probably not, but I can't rule it out entirely. Do you know what your ammonia, NitrIte and NitrAte readings are? If you don't have a test kit, don't panic, you can take some tank water in a clean jar down to Petco, PetSmart or your LFS and ask them to test it. I know Petco and PetSmart will, most fish stores will. Don't settle for "this is a bit high" or "It's fine!", get the numbers.
What kind of filter do you have and what is your normal tank maintenance? The more of my questions you can answer, the better answers I can give you.