Holy Call Back, Batman!

So I send 2 resumes out (1 last night, 1 this morning) and received call backs from both of them! I could hardly believe it! I have one interview set up tomorrow PM and don't know whether to be nervous or excited. First of all, I haven't received call backs that fast EVER (LOL) not to mention having an interview with one day of the call back! Just thinking about it makes my stomach all sorts of funny! I am excited, however I didn't expect anything this fast. I haven't even put together my "take it or leave it" pitch for my current employer! I know what you're thinking - I haven't even been offered a job yet. I know that and it'll probably be my luck that I'll get lots of first interviews and not make it past that. But jesus, this is quick!