Welcome to the forum. Thanks for your question.
With a negative duo test 4 weeks after the last possible exposure, you can be 100% sure you didn't catch HIV. Your symptoms don't matter; the test result proves HIV isn't the cause. I disagree with your discription of only 95% accuracy of the duo test at 4 weeks; it's 100%. Below I've provided the link to a thread that discusses this in more detail.
http://www.medhelp.org/posts/show/1704700
I will add that most female escorts (expensive sex workers by appointment) are very cognizant of safe sex and rarely have HIV. And oral sex is never a risk factor anyway, whether or not she "ejaculated" in your mouth. (Female "ejaculation" in fact is just a squirt of urine, and urine doesn't carry HIV.)
So no worries. You really don't need another test at 6 weeks. But feel free to do it if another negative result will give you greater confidence. But I am confident you didn't catch HIV; any additional testing will also be negative.
I hope this has helped. Best wishes--- HHH, MD