You would not be testing for the alcohol level, you would be checking that the fermentation had ended. You need to take 2 gravity readings, one then another 2 days later. If the numbers are the same, fermentation is done. You then have several options. Bottle the beer, transfer to secondary for clearing or leave in primary for clearing.
So, yes you should have taken hydrometer readings. It is not the end of the world though. If fermentation is still occurring it will finish in secondary. This is not optimum but you will get beer. With no other problems it will probably be good beer.