Happily, if you used the condom correctly, you are not at risk of hiv and testing is not medically warranted. There is no risk of infection through fluids coming into contact with your stomach or bottom of the penis, because this is only skin exposure, which is not a means of transmission. Hiv infects through the urethra of the penis, which is not exposed if a condom is worn.
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Don't worry.

Theoritically speaking, the risk of infection occurs due to exchange of body fluids like vaginal fluid, sperm, blood and saliva.

However, the percentage of possibilty varies from one body fluid to another. Morever research shows that male to female infection is more possible than a female to male infection.

If you are unsure of what you did, and your possibility of infection, to be on a safer side, you could test yourself after the window period. In the mean time, you could protect your close one like your gf or your wife by staying away to make sure that you dont infect them too.