Where can the uterus be felt @ 14 & 22 weeks?

My girlfriend is either 14 or 22 weeks pregnant. Regardless of a nurse @ PP (Planned Pregnancy) telling her she was not pregnant, as well as 10+ negative tests, she continues to worry herself. Which I understand, being pregnant @ such a young age (15) is an absolutely horrible thing to contemplate. Time & time again she brings up the possibility that she may be pregnant, granted the nurse & the tests stating otherwise, & time & time again I do my research, bringing about points that disprove the possibility that she's pregnant. Now, onto the question: Where can the uterus be felt @ 14 & 22 weeks, & what does it feel like? She is uncertain of what to feel for, & she is concerned that a region to the top-right of her pubis is her uterus. What she is feeling is what I believe to her either her obliques or the lingual ligament, which starts @ the pubic tubercule (the top border of the pubis). Can anyone help me out w/ this? I would really appreciate it. Thank you.

Just below/just above your belly button and it feels kinda like an orange or a grapefruit. A little squishy and firm at the same time. If you have her lay flat on her back you'd be able to see and feel what I'm talking about

the baby would be below her belly button.....between her belly button and her pubic bone.
but she whould DEFINATELY feel kicking at 22 weeks and definate *fluttering* at 14 weeks (feels like gas bubbles)

well I agree with the health care professional although this happened to me with my first pregnancy all the test I took at home all read neg. even a check w/P.P and two other health care professionals showed neg. even when I started to show they told my mom that it was my hormones, not until I was about 4 to 5 mos. they than discovered I was indeed pregnant, so maybe I'll take that back. Well mine is just below the belly button baby started moving @ 16 weeks or earlier I'm 23 weeks now and showing.