Welcome to the forum and thanks for your question.
Below is a link to a thread that discusses condom performance in great detail. Although a few years old, the information remains accurate, with one exception: condoms are somewhat less effective against genital HSV-2 infection than described in the thread:
http://www.medhelp.org/posts/show/665887
Oral sex carries no HIV risk even without a condom. With an intact condom in place, there is no chance you were infected. If the head of your penis and the urethral opening were covered, you have nothing to worry about. To your specific questions:
1) Anybody can say anything they want on the web. Not only do some people give misinformation intentionally, but many people mis-judge when and from whom they were infected. The fact remains that there are no proved cases of HIV transmission by oral sex from an oral to penile partner. Some other STDs, especially herpes and HPV, are sometimes acquired despite condoms. But this is from vaginal or anal sex, not oral; and typically occurs because of skin contact above the condom -- which is generally not an issue for oral sex.
2) All people who are sexually active and non-monogamous should have routine HIV and STD testing (gonorrhea, chlamydia, syphilis) from time to time, like once a year. If you haven't been tested recently, this would be a good time, while it's on your mind. But not beause of this particular event.
3) Zero risk for all practical purposes.
I hope this has been helpful. Best wishes-- HHH, MD