Hi. Im Not Sure, But I Think I Have A

Hi. Im not sure, but I think I have a yeast infection. Iam not on any meds nor have I been any time recently. I just got over my period and that seems to make it worse. Actually, the only time I have symptoms is when my period is just about over. I use ob tampons and have for many years. I have never had any problems with them. But now it seems to irritate me really bad down there. My whole vagina area is extremely red, inflamed and itchy. It also has a nasty smell. I shower every day. What could be the problem? I cant really afford to go to the doctor But I don't want to use yeast infection cream if that is not what is wrong. Please Help!!