If you are worried you might have contracted HIV, I would recommend that you take HIV spot test. Although the sex worker in question seems to have had mastitis because she was lactating. The different sizes of breast does happen when a women is lactating. The H. Pylori is a normal resident of the stomach present in about 80 % of the population. In a few people they cause gastritis and ulcers and need to be treated. It doesn't have any relation to the HIV infection. As you are worried about the appearance of rash I would recommend you to get a HIV test.
I would recommend the following-
1)I would advise you to not visit sex workers in the future as the risk of contracting sexually transmitting disease is very high.
2)If you do visit a sex worker makes sure you use protection and follow safe sexual practices.
3)Get an HIV test from the nearest laboratory to put your mind at ease. I would also recommend a complete blood count and a physical.
4)If you have not completed the triple regimen drugs for H. pylori infection, complete the entire course. H. pylori are very resistant to treatment and incomplete course of antibiotics can make them resistant to treatment.
5)Eat a good balanced diet with good portion of proteins carbohydrates and vitamins. Also follow a strict regimen of exercise.