I was told it could be a yeast infection

Hi I'm 20 years old. I recently had a baby almost two years ago. I've had implanon inserted and everything was fine. But now I have no period im tired and moosy and gaininh weight and I'm having vaginal discharge and a small odor at random time . My inside of my vagina feels sore as well it's been OVER three weeks since interaction My discharge is a white/ creamy when I wipe. I was told it could be a yeast infection or multiple Things! Im not sure what this could be?!?!