I had a single small red/white bump on soft palate for a couple days and its gone. in hiv mouth sores, would there only be one or would it be more?

More than one likely: There are more than one type or mouth sores usually related to hiv. Most have more to do with being immunosupressed- like candidiasis (ulcers caused by yeast infections), cold and herpetic ulcers as well as leukoplakia ("hairy tounge"). The onset of a single small lesion that has healed is not an indicator that you have contracted hiv. If you are still fearful, the best remedy is testing.

Maybe: You could have one or more sores. The presence of them doesn't mean you have hiv. Your best test is a blood test.