just got my letro drops and i need to use them asap, only problem is i've never used drops before, i know how im going to take my dosages (.5 mg for the first one). on the bottle it says 2.5 mg/ml , and there's no measurement markers on the little dropper... so how the FUCK am i supposed to know how much im taking!? can i use a pin and convert ml to cc's?? someone help me please, and give me DETAILED advice so i dont die, thanks!