This is what 90% of fosh keepers do since most people have never heard of cycling. Don't feel bad, when I was 4 I dumped a bag of flour int the tank and cranked up the heater because I was hungry. No survivors but atleqst my mom caught me before I thought they were done.
The dumbest thing I ever did was listen to the LFS when they said, "sure that porcupine puffer will be fine in your 10 gallon"... Upgrade came quick after that...