Lap dancing is a pretty safe way to have sex.
Some STIs, such as genital warts (HPV), herpes and syphilis, can pass with grinding but there needs to be direct skin to skin contact.
You had your underwear on with the first lap dance and there was no skin to skin contact, so there should be no risk of STIs.
With the second lap dance it sounds like the woman had her underwear on. There should be no risk to you even though there was brief contact with your penis – because her skin was covered.
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