Help!...UTI or infection at 26 weeks???

For the past few days I've been experiencing some itchiness and irritation which is very uncomfortable. Possible change in smell but it's hard to tell. I've never had a uti or yeast infection before so I'm not sure if that's what this is? My OB is totally booked because of the holiday and my family doctor said to contact my OB since there are certain medications I cannot take. I'm not even sure that I have anything, but I don't want to be miserable over Christmas if it ends up being something! Not sure what to do now?? Any advice?