What are the side effects of the progesterone implant?

I'm 17 and have been on the implant since march 2009 ive lost my leaflet about the side effects ive been getting really bad pains before my periods for the past 8 months im booked in for and ultra sound on the 10th to check for ovarian cyst :/ :( ! Also ive recently been getting what i can only describe as a tapping/t feeling from the inside ( i think its my veins and the blood not getting through properly) of different places in my legs and arms and you can feel it and see it from the out side it feels the same as me tapping my finger on my skin kinda thing sorry to be vague! any way i want to know are these side effects of the progesterone implant? thank you if you answer this :) 10 points for best xxx