hi Lucy,
well my measurements are 30 inches under my boobs, and 38 inches at the fullest, so same 8 inch differance as you.
I am wearing a 34e so i am guessing that you could end up a 32dd or 32e or you could try a 30e or 30f
It is still really early days for you, so try and be patient and wait untill you are at least 6 weeks as you could change size still. It’s best to just try on lots of bras, and see which is the most comfortable. Also you will find that you will be different sizes in different shops, which is why it is so difficult to say what size you will end up!
Hope this helps…. enjoy your new boobies!!
xx