Even without a condom, if she was HIV
infected (and you have her assurance that she was not) the chances of getting HIV
from unprotected oral sex are less than 1 in 10,000. With condoms the risk is far lower, had she been HIV infected (and she was almost certainly not).
At the time you were tested at 2 weeks, over half of HIV infections that are going to be positive would have been. At four weeks that figure rises to 85-90%.