Condoms are 100% safe when used correctly by that if your penis head is covered. As yours was you have nothing to worry about at all. Nothing that you have said would give any concern to being exposed to HIV.
Also, its very very unlikley they have HIV. CSW get tested for HIV and std's to know their status, they also use condoms to protect themselves from you.
As for testing, well you didnt have any risk of HIV so you dont need to test at all.
Hope that helps