Welcome to the Forum.  I am going to do my best to convince you that your symptoms and signs at varying locations are not an STI.  Here goes:

1.  Your risk for acquiring any STI from the exposure you describe is low.  Most people, even most commercial sex workers do not have HIV or other STIs.  Further, when they do, acquisition of infection from receipt of unprotected oral sex  is statistically considerably less common than from unprotected genital-genital contact. 

2.  Even if your partner did have an infection, most single exposures do not lead to infection.  the best data are for HIV where transmission is estimated to occur, on average, once for every 1000 exposures and for gonorrhea where infection occurs as often as once in every five vaginal exposures for men having unprotected sex with infected partners.

3.  You used a condom.  Condoms are highly effective.  There is no reason for concern about breakage.  When condoms fail, they break wide open leaving no doubt that they have failed.

4.  The abnormalities you have described are at varying locations around your body rather than in the same place.  The sorts of migratory and varying signs and symptoms you describe are not suggestive of any STI.

5. Lastly and most importantly, you have been tested with highly reliable tests at times when tests will provide accurate results.  I urge you to believe them.

Thus, to summarize, for all of the reasons mentioned above, you are more likely to be struck by lightning while reading my response than to have acquired an STI from the events you describe.  My guess is that due to heightened concern and perhaps guilt, you are looking for "any" sign of infection and attributing the sorts of lesions, stretch marks, etc. that we all see  and have from time to time to possible STIs acquired during your dalliance.  I urge you not to worry further and to focus on moving forward without concern. Further testing would be a waste of time and money.  EWH