Welcome to the Forum.  I will try to help.  You report two exposures to commercial sex workers who may have had an STI, including HIV and are concerned about this.  I congratulate you on your use of condoms for all exposures- the fact that you used condoms for these exposures will greatly reduce your risk for acquiring any STI. Condoms are the most effect way to prevent acquisition of most STIs and although they are not perfect, they are very good.  Currently, with regard to HIV, it is estimated that IF one of your partners had HIV (you do not know that they were and it is statistically unlikely that they were), the risk for HIV would be less than 1 exposure in 1000 unprotected genital sexual exposures.  Using a condom reduces that risk more than 99% more (the statement that they only provide 80% protection when used correctly is wrong), making the risk for HIV from a single condom protected exposure to an infected sex partner somewhere between 1 in 1 million to 100,000.  This is not something to be too worried about.

As for your specific questions:

Sorry if I was confusing.  I recommended the test for your peace of mind, not because I am concerned that you acquired HIV from your condom protected exposures. 

Unfortunately, some of the other infections (chlamydia in particular) can be asymptomatic so, if you want to be completely confident, I would test for the others.  Hope this helps.  .  EWH