I do not know what to tell you about questioning missing a dose (whether to take half dose, etc), but would strongly suggest you obtain a weekly pill organizer such as on this site:

http://www.drugstore.com/products/pr...goobase_filler

and only use an alternative source for your pills if you are out and the container not available. Or better yet, if you know you will be out, take the dose you will need from the container with you.
In answer to your question about missing a dose, ask your doctor or his nurse what to do. best, madelyn