I had unpertected sex last sat and sunday. I am on mirana, but out of fear I took a morning after pill on Tuesday. could I be pregnant, or am I just freaking myself out?

No form of birth control is 100% effective so statistically it IS possible... but its also way way too soon to know. Its still possible you CAN get pregnant as its only Tuesday night, that's three days and it COULD happen up to a week after. But you would be another month at a minimum to even take a test to find out. The odds are low... but they aren't zero.

So more than likely I'm freaking out over nothing

So more than likely I'm freaking out over nothing

Yes. However, you will not know whether your fears are groundless until you miss your next period or a doctor can confirm you are or aren't.

Can happen, but very unlikely.