vaginapagina | Breast Ultrasound?

I've had a lump in my left breast, somewhat below the nipple, for about a year. When I first found it, I noted that it felt just like a marble, and when I Googled "marble breast lump" I got lots of reassuring hits about how that was overwhelmingly likely to be benign, especially at my age (was 20 at the time), but that if it started hurting or changing, I'd have to go to a doctor.

Well, in the last two months it's started hurting when poked and aching for the two weeks before my period, and unless I'm imagining it, it's gotten a little bigger. Anyway, I realized that meant I should see a doctor about it, so I did, after procrastinating for about a month because I'm not comfortable with being undressed in front of strangers. The nurse who examined me said it was about 1cm in diameter and ordered an ultrasound because she thinks it's a fibroadenoma (which, from what Google tells me, is a benign tumor, but can indicate a predisposition to breast cancer later on, and is usually surgically removed).

I finally scheduled an appointment after an unpleasant runaround with my insurance (first I could get it done nearby, then I couldn't, had to cancel the appointment, and make an appointment that will be very difficult to get to). Said appointment is on Monday, and I'm flipping out about it, mostly because it looks like I won't be able to have my partner with me (because he has to be at work). Have you ever had a breast ultrasound? How old were you? Did it hurt or was it uncomfortable? How long did it take? What was the outcome? Please share any details you have about the procedure. I'm mostly worried about being alone and feeling exposed to a stranger (I can't choose if the technician is male or female either), but also (obviously) about the diagnosis. Thanks, VP!