With bitter almonds, 8 - 32 almonds will give you the lethal dosage of cyanide. Bitter almonds yield about 6.2 mg of cyanide per almond and the LD50 for cyanide is 50 mg - 200 mg.
This applies only to bitter wild almonds: considering that you're not dead, you most likely ate domesticated sweet almonds, which apparently do not have this problem. The sale of wild almonds may be illegal, in fact, though I can only find blogs and internet comments alluding to this.
From wikipedia
> Wild almonds are bitter, the kernel produces deadly cyanide upon mechanical handling, and eating even a few dozen at one sitting can be fatal.
...
> While wild almond species are toxic, domesticated almonds are not;