Welcome to our Forum.  I will do my best to help.  In general, among the wide variety of possible penetrative sex acts, cunnilingus is the one which is biologically most inefficient (i.e. a person is least likely to become infected, if they do that activity with an infected partner).  When you add that the FACT that most exotic dancers (and commercial sex workers- admittedly there is some overlap) do not have STIs, your performance of oral sex on this partner carried very little risk of infection.  As an FYI, I know of NO cases of HIV documented to have been acquired from performance of cunnilingus on an infected partner.

Having said all of this, getting a sexual health check is always a good idea and the negative results that I anticipate you will get should help to provide peace of mind. 

As for your lip lesions, from your description they do not raise concern for STIs that cause lesions- they are in no way suggestive of herpes and it is far, far too early for HPV to be manifest.  My suspicion is that you may have looked closer than might be normal and noticed something that has been present but went unnoticed in the past.  If the lesions persist, you may want them to be looked at by someone who specializes in the oral cavity (i.e. an ENT specialist) if your own doctor's reassurances are not helpful.  Th, e topical materials and antispetics you are using may be causing more irritation than helping.

Finally, I advise you to stay off the internet.  While well intended, the statements are often overly alarmist and may get their facts wrong.

I hope these perspectives are helpful. there is really very little for you to be worried about