Exactly what is your preferred weapon of self-defense? Have you considered having a stun gun? They make them quite compact today if that's the thing you would rather carry. Additionally, there are other options, like pepper spray.
Might I suggest having several option on your person when it comes to self defense. It may be a good idea. In case you can't get to one, you can use the other. Or you could utilize both in an attempt to make sure you are safe and sound in a situation which is threatening. One never knows when a stun gun or identical self defense product might be useful.