Btw... I'm 19 weeks and if I personally had a yeast infection right, I'd probably go ahead and just shove some yogurt right in there no hesitation... Lol it is a little messy though, so pantyliners are your friend.
So, I've never been pregnant before... I don't know what is okay in pregnancy, but I've always just used plain Greek yogurt for yeast infections. My doctor is absolutely useless for things like that. If I call for an appointment she won't ever see me for something like a yeast infection...well, I mean she will bit they will schedule my appointment 30 days from when I need it. So, instead of shoving medications into my vagina I rub cold Greek yogurt around the outside labia and it cools really well and instantly stops the itching. I also put it inside my vagina... Taking probiotics capsules helps too. Annnnd eating garlic. 2-3 cloves mashed up in something fatty (avocado/butter) and eat it every day until the infection is gone. Garlic is a natural anti microbial, anti viral and here's the important one for you, anti fungal!
Anyway, I'm not a doctor... But I hate going to doctors and I try to avoid pharmaceutical medications at all costs (including over the counter)... I've had rxns as simple as rashes, to welts to my bladder stop working from different medications so... I decided to start studying as a certified herbalist and I've been using natural healing and 9/10 it works better/faster than the doctor's medications.
A second opinion is what you need :) And your doctor doesn't even have to know that you got another professionals advice!