Is it possible to waste too many access cards on XP bonuses?

It looks like you get one Access Card per level, and you can use these on various things in the armory. There's a clearly set number of things to unlock (once unlocked, they're unlocked), and there're a few temporary XP bonuses that you can spend these cards on to earn more faster. Since there is an achievement for level 100, I'm assuming that's the maximum level you can reach (please correct me if I'm wrong on that), which would suggest a limit on the number of access cards you can get. If there is a limit, then if you spend too many on XP bonuses, you won't be able to unlock everything.

Is there a finite number of access cards available? Is it possible to waste so many on XP bonuses that it's impossible to unlock everything in the armory? If so, what's the limit? How can I tell if I've wasted too many, or if it's still safe to spend them on XP bonuses?