Check the Mode that you are using.
Many drones have the option to be Mode 1 or Mode 2.
The transmitter controls do different things depending on the Mode.
Sometimes if you are not careful, you can accidentally change the mode. And control goes all astray. 🙂
Google "drones Mode 1 Mode 2"
Take a close look at the User Guide/Manual for your Sky Viper. And the transmitter settings.
Another thing to take a look at is the configuration: Could be "+" or "x".
Update: do not ignore the fine tuning (trim) controls. They can be very sensitive and it does not take much of a change to make the drone want to go all "frankiendrone" on you.