You have one knife on your person. Good for you. Two is better. Three is better still. More, if you want to have self-defense options that include edged tools/weapons. No, really. Close range knife “fights” mean BOTH will be wounded. If not defending against a firearm, ranged knife defense – practice throwing knives? Sure – can be an exceptionally effective option.
Note: knife wounds are more likely to result in fatalities, so make absolutely certain you cannot remove yourself from danger without seriously wounding an aggressor.
Aside from self-defense options, knives are pretty close to being the ultimate “frustration-free packaging” tools, among many, many other uses, and the right knife for the job can make a big difference.