You probably have those things and you just dont even know it. You can test for herpes to see if your body has antibodies to it. You may have even had an outbreak in the past and you just didnt even realize it. Most of the population does have those two things and are simply carriers and never even have HPV or Herpes outbreaks at all. You definitely have HPV if youve fucked more than 5 people in your life because of your age and therefore havent been vaccinated against it like these younger generations.
And if you take your medication and are POZ, remain undetectable, and healthy, your immune system is no more compromised than a person that doesnt have HIV. Getting something like an STI (Chlamydia, gono, etc) is not that big of a deal. I probably get fucked by 100-200 people before I ever happen to catch one of those, and then its just a simple visit to the doctor, and most of the time I wont even have many symptoms. Everybodys got or gets something from time to time.
The real problem with barebacking is taking on the risk of contracting something that we havent seen yet and is just beginning to transmit sexually like HIV did for example, or has mutated to the point antibiotics no longer can treat it. There are strains of gono which are very, very difficult to treat.