Im applying everywhere!! When will they get back to me.

So I just completed my phlebotomy course At MCC and the Internship @ St. Joes. Now Im looking for a job and applying to all local hospitals & doctor's offices.. and no word back. Well, one - Dartmouth in Lebanon called for an interview but i live 2 1/2 hours away from them .
I guess my question is how long until someone will get back to you? I did all the applying online over a week ago.
Another question - Should I wait till i get a job in the field (if i do) or should i just look into getting my certification right away?

Thanks for reading and any input
<3