Roman plays and in particular Plaute's plays abound with profanity as would have been used in the late republican period. Some of the most common words used are "Hercle" (by Hercule !) or "Pol/Edepol" (corrupted forms of "Polluce", by Pollux).

A good example is the Asinaria around verse 842 : Argyrippe managed to buy a sex slave / courtesan with the tacit help of his father Déménète -- who now wants for his share of the deal : a night with the courtesan. Argyrippe swears "Atque ego quidem hercle, ut verum tibi dicam, pater, ea res me male habet"

This is interesting as this kind of comedies would give us a good indication of the kind of profanity that would have been used in street Latin of that era. As you can see a swearword like hercle is used pretty much like modern US english would say "oh God" or "f*ck this".

Unfortunately we do not have recordings of what a Roman would have said and I do not know of any play where sexual intercourse would take place onstage (Roman comedies are not really prudish as you can see from above but it would have been somewhat improper).In any case it is quite easy to picture a character like Argyrippe saying "Hercle" after some fun.

We do know from Catullus how Romans would say they were exhausted by sexual activity : in Catullus 6, the author speaks of "latera ecfutūta", funds exhausted, literally "fcked away" (notice that it is the same construction as when modern Russian says выпить свои денги -- not a native but it means to drink away one's money). In Catullus 29 he similarly speaks of a "mentula diffutūta", i.e. a male appendage similarly "fcked out". Surely a Roman could have said "diffututus sum" or something in that vicinity.