Help advice needed

I have been a nurse for almost four years. The unit I currently work on is a busy med/surg/tele floor. I have been called into the office 4 times now for my "attitude" I have been the first person to admit when I have said something that could have been taken wrong. Now I feel like someone is nit picking. The manager even said that people have issues with general conversation. With things such as....When you guys are all just talking and compainring the types of patients you have taken care of you need to stop comparing. She says its like I am always trying to one up everyone. I have traveled in the past and have worked other types of units therefor I have a lot of experience to pull from.

I feel like I can't even talk anymore. Innocent stuff is starting to get taken wrong and twisted. Yes I do at times get an attitude. I have appologized for it. My manager says its my tone.

Here is my question....How do you handle getting irritated or even mad at work without having the tone or your voice come accross as innapropiate. She is to the point of doing a level one correction. I am looking for ways to catch myself and save my job.