Anxiety over pregnancy scare?

Ok. Here's the situation. I am 33 and the woman I was dating is 54. She has gone thru menopause close to 3 years ago. We had sex in Mid August, let's say Aug. 9th, 3 days later she says she feels pregnant. So we get a couple packs of pregnancy test. We do a test 9 days after we had sex and again 12 days after we had sex and they both say negative but she is feeling nausea, she cannot eat anything and when she sits up it feels like everything is spinning. During the second test we did her urine was cloudy as well. She went to the doctor because she wasn't getting better and the doctor told her that she had vertigo. She started taking the meds for that and now she is better. She says she had mistaken being vertigo for being pregnant but I still feel uneasy and uncomfortable about if she is pregnant or not. She doesn't believe she is but the scare still has me feeling anxiety and she doesn't want to take another pregnancy test. I'm assuming she isn't pregnant but at the same time I still feel worried because we haven't done a 3rd test. Any thoughts on it?