Is it necessary to get tested for HIV if the wound dressing was done with a gauze used by an HIV patient?

Hello doctor,

I had a car accident and had a serious bleeding wound on my knee with a size of 2.36 inch x 2.36 inch. I went to an emergency room in a small hospital in a rural area to get treatment. The nurse cleaned my wound and it was bleeding. After cleaning the wound, the nurse used a gauze pad to cover my wound. I noticed there were some stains on the gauze pad. Because she did it so quickly and at that time it was so painful, I did not ask her about this at that time. When coming back home, I started to realize she might accidentally take a gauze pad that was used by other people minutes before and the stains I saw might be other people’s blood. Since this was a very small hospital in the rural area this kind of mistake might happen. I know the stain might be another medication or something, but let us just assume it is another patient’s blood. I am worried about what if the gauze pad was used by the other patient with HIV(Human Immunodeficiency Virus). His blood on it deeply contacted my wound for hours, which might cause HIV infection. Do you think there is such a risk, and do I need to do HIV test?

Thank you.