Same question as Diana_K, Is it a native plant? or did you purchase it at a store or nursery, or did you get it in a trade & from what state and County?.
The reason for those questions is to help facilitate it's origin in nature which helps tremendously in ID'ing it.
And yes, please take a side view close-up of the larger spines. I have a suspicion on what it may be, but I want to be surer.