painfull lymph nodes

Hello, I have begun to notice a few painful lymph nodes, like they are swollen, but they don't feel real big. I noticed this in both armpits and in my groin/upper thigh on my right leg. The pain isn't really bad, but it's noticeable. I worry about diseases like Lymphoma and HIV because I know swollen lymph nodes in multiple areas of the body is an early sign of both of these diseases. I know injury can cause swollen lymph nodes, but I haven't had any real injuries recently except maybe a bruised muscle in my right arm from messing around with a friend a couple days ago, but I don't think this would cause painful lymph nodes in both my arm pits and right groin, but I don't really know. Also just to note I haven't been sick recently except for a little sinus congestion for about 2 days about 2 weeks ago so I don't think the swollen lymph nodes would be from that. I'm basically trying to figure out if all this could be caused by some little injury or if I should worry more about these lymph nodes or what. I would really appreciate whatever help you all could give me, thank you in advance!