You are okay. You are freaking out because you now know her status, otherwise you would by now have forgotten you slept with that lady, because you followed the GOLDEN RULE of CONDOMISING.
Is she on treatment? if she is, then it would create an extra layer of protection. I think you should be fine as long as the condom was used correctly.
Yes, I agree. The condom protected you from HIV and was considered safe sex. There is no reason to worry or test after that if you used protection.
Those condoms are made from polyisoprene which provides an effective barrier against HIV and most other STDs. You did the right thing using a condom, congratulations! As long as you always use condoms and they remain intact then you have no worries for HIV transmission.