Too many questions

I have been working on a heme/onc/BMT floor for about 3 months now and while I can tell I'm getting more of the hang of things, I feel most days that I'm still running around like crazy despite having a good brain sheet, etc. There is SO much to learn and I always try to find the answer by myself before I ask any of the other experienced nurses but I just feel like sometimes they're getting really annoyed with me. I guess this is just more of a rant, as I'm ready to not feel as clueless all of the time. I know they say it takes about a year to feel comfortable, but when does it start to get better?
Um - I think you already answered that question for yourself.... "I know they say it takes about a year to feel comfortable . ." Trust in the information and advice you are being offered by your more tenured colleagues. IMO, your feeling about 'annoying' them is probably due to your own lack of self confidence rather than reality. It would be far worse to forgo their validation because you don't want to aggravate them.
I think a HUGE part of the reason why people say you'll feel more comfortable after a year is because a year from now, you'll have hopefully asked most of your questions. You won't need to ask what to do about certain meds or where things are or how to handle a situation, because you've already asked. Questions are good. I guarantee your coworkers like answering your questions more than they would like seeing you suffer or, worse, seeing a patient suffer.