I cant believe that no one has replied to you in 7 days. That is not normal as we have a lot of knowledgeable people here that usually want to help, especially to help a newbie.
First... welcome aboard...
For starters I have to admit that I dont know much about Blackhawk bows... other than the fact that they have been around for quite a while and have stood the test of time. If your Nighthawk is solid, no delaminatios, limb twist, or other dameges; it should be safe to shoot and will probably give you many years of good service.
As far as the broadheads go, if they seem to be intact, then they are probrbly useable for hunting... just make sure you put a super sharp edge on them before hunting with them. Keep in mind that the broadhead is the most importand part of your bowhunting setup... the rest is just the delivery system. Too many new bowhunters get a set of broadeads and assume the factory sharp is good enough. Dont fall into that hole.
I wish I could provide more information but I a limited by my lack of knowlege of Blackhawk equipment, and the sparse information you have provided. If you could post a few pictures of the bow and broadheads, it may help to get someone more knowledgeable to jump in with more info.
Good luck in your new interset, and feel free to ask any questions you may have here. You will normally get a better reposethan you have.