Good questions and you outline a good plan. A few comments:
1. Do you definitely know you were tested for HSV? Often when folks ask to be tested for "everything" they are tested for gonorrhea, chlamydia and perhaps syphilis and HIV but not for HSV.
2. Telling what you have without testing or a direct exam is difficult. There are several possibilities. The lesion you describe DOES sound as though it could be HSV but if it is, it sounds in many ways more like a recurrence than a first episode. Syphilis can be painful if there is a bacterial infection on top of it. Finally, Aldara certainly can cause erosions. Seeing your doctor and requesting both herpes testing and a syphilis test is a good idea. If the sore is still present you may want to request both a swab test for HSV (i.e. a culture or, even better yet, a PCR test) as well as a type specific test for HSV such as the HerpeSelect. A syphilis blood test will tell the syphilis story and the issue of Aldara reaction will need to be dealt with by examination.
3. Notifying your partners is always a good idea as it may provide a clue to what is going on with you. On the other hand, I and I suspect you, do really not know what is going on yet and thus you will not be able to inform your partners about this. One approach might be "I have a penile sore and in talking to the doctor, there are several possibilities including a medication reaction, herpes or syphilis. Are you OK? I will let you know as soon as I have a clearer idea of what is going on." or something to that effect (not to try to put words in your mouth).
4. Herpes is common. One in 4 American women have genital herpes (as do 1 in 5 men) and of those, 9 out of 10 do not know it. the absence of symptoms recognized as herpes, sadly, does not assure one that they do not have herpes.
5. HIV screening is always a good idea. Nothing you have mentioned raises specific concerns but we recommend annual testing (for HIV and STDs) for anyone who has had two or more sex partners in the past year (we consider this to be health maintenance- we also recommend you get your blood pressure and cholesterol checked regularly).
Hope these comments are helpful. Please let us know what your doctor says. EWH