Hey there. It is so hard not to worry. But he really does need to get better before starting the tarceva so you just need to focus on that for now. Days here or there really can't make that big a difference in the larger scheme of things. So as others have said, you just need to take it one day at a time and deal with what you've got. It's hard to do though. So take a deep breath and know that there are many here hoping for a quick recovery for your dad.
Sandra