No, sorry, but you'd be wrong here. If it's a Mk 3 size (the common size for personal self-defense), or even Mk 4 (the size most cops carry on their belts), you have only a limited number of bursts. OC is not comparable with a firearm, which can be reloaded; an OC canister cannot be.
Did you get the .7 formulation or the 1.3? The .7 is effective, but the 1.3 reigns supreme. My personal recommendation would be to get the "360" canister, which uses an internal bladder and can spray effectively no matter what position one holds it, while the more common nitrogen-propellent canisters typically have to be held upright. Additionally, you'll get only about half as many bursts as the manufacturer claims, and as far as distance goes, this is why you should order the inert trainers. 8 feet is about the practical max distance, although again, the manufactures will claim 10 to 12 feet. Wind and rain, obviously, will affect results.
Don't bother with the .2 or .4 per cent formulary. .7% is about the minimally effective on the market. Also, hope you shopped around, because prices get stupid, with some retailers charging more than twice as much as others.