I was on these pills several years ago and stopped because I found out my biological father died from blood clots that traveled to his lungs. My doctor suggested I go back onto them and I am having major anxiety about developing blood clots. I just took 1 pill today and now my calf hurts. Now I'm freaking out. I'm going on a trip on the 27th, my first plane ride and am freaking out about blood clots...please help.