You are probably hearing alarms and getting messages about Vampires. No Dracula is not modeled in the game, Vampire is a generic term representing incoming missiles.

You may note that one of the contacted units has gone red as well. This means you have identified it as the unit who fired the missile. If it did not go red, you did not see who shot the missile but are now only concerned about the missile.

Your best course of action is to: Drop to minimum altitude ("F2") fast, tick terrain following, adjust your course so you're in the valleys and not following the mountain tops.