Can my 250 watt amp power a pair of 10' subs?

yes it will and you have done the correct thing which most people don't you have an amp that is lower power than your speakers this is good because most people will buy average speakers with say 300-600 watt power then go and buy a 3000 watt amp and this is just asking to blow the speakers lol as long as the speaker power is more than the amp it will be fine mate