My feet grew with both kids. Haven't grown with this one though. Don't feel bad!
My feet swelled a bunch especially in the last weeks of pregnancy, but my shoe size didn't change in the long run. I wear a 7 and was wearing 8 in my last month, but once the baby was born I was back to a 7. (In other words, it's doubtless water retention rather than the rearrangement of foot bones or anything like that.) See if you have any pals with feet one size larger than yourself, who have some walking shoes they don't use very much (I had a pair from a tour we took that involved tons of walking, and was able to wear them for a while before I grew out of them, and noticed how good they felt), or just bite the bullet and buy a good, structured pair of supportive shoes. Don't buy cheap or thin ones, they will really hurt in the long run. But something with arches, and firm sides. If you work in a bar, sometimes catalogues come through with food-handlers' clothing in them that advertise really good-looking supportive shoes. Of course, if there is a dress code that forces you to wear heels, that suggestion is unrealistic, except that there are a lot of other bars that don't do that and could use a good person. (And besides, I don't think a business can force a pregnant woman to do something that hurts.) Anyway, get new shoes! Good luck.
I have heard that some women's feet grow during pregnancy. I just didn't know if that was a myth or if it was true. As long as your toesies are comfy go for it!
Do what you gotta do my dear! Maybe think about investing in some extra support like Dr Scholls inserts for your soles? Try to put your feet up as often as you can, not like up high but when you sit even just putting them a couple inches off the ground should help a lot!