RYL Forums - could use some advice tonight...or someone to tell me I'm not overanalyzing

I hope this is ok to post here. Here's my issue/problem. Someone just tell me if I over think this, if I shouldn't be doing this or whatever! I have an interview on Thursday with my same company just for a different position. It's not life or death, I still have a job regardless, this would just be better experience. The people doing the interviewing are my boss and my boss's boss. I have a normal boss/employee relationship with my direct supervisor. With my boss's boss, we talk about lots of stuff. She knows most of my issues...well actually, I think all of them. Things have just come out as we talk and ever since she saw my scars, we talk alot. Not always about that stuff, it's work, food, vacations, really it's anything. Anyway my point is that I don't care what others think about me talking to her but in the back of my mind I always wonder if she thinks I am doing this to get ahead or something. It's been going on LONG before this interview came about, this whole thing started a few months after I started working there in April. I just felt comfortable around her. She always knows the right thing to say. Anyway, today she walked in the break room and I was there and I had snapped at this girl who was asking about my interview. She had good intentions but I have so much going on right now that I just can't handle people grilling me. I was like "wow I did not mean to snap at her..." She told me it was ok and not to worry. She knows I don't like this girl. Then tonight, we were talking and I told her I apologized to that girl and I didn't mean it because alot was going on. I told her that I had an anxiety attack at work (which I did the other day) over people constantly trying to talk to me about this interview. Is that too much? It just kinda came out but I don't want her to think that I have other motives. I can't help it that I tell her so much crap. It just comes out and I trust her more than most everyone. I really sometimes just need someone to talk to who will listen, and she does. I don't know what to do because she is in a supervisor situation and I can't tell her how much I feel comfortable talking to her. Our emails and conversations about strictly work are completely on a professional level. She is not one to play favorites and I don't believe her personal feelings about someone would influence who gets the job, do you know what I mean? This is totally rambling but hopefully someone can understand and tell me what they think. If you got through this, thank you in advance!!!