That pressure feeling when peeing could be a few things, like pelvic floor weakness or something your gynae really needs to assess properly, so I wouldn't want to guess whether it's prolapse or not. Since your gynae appointment is still a month away, it might be worth calling the clinic to see if they can bring it forward, or just popping by a polyclinic in the meantime so a doctor can take a look sooner. One month postpartum, your body is still healing, and it's better to get it checked early than to wait and wonder.