Is It A Matter Of Concern That The Baby Is Suffering From Diarrhoea And Producing Less Urine Even After Having Fair Amount Of Fluids?

After a plane ride this weekend my 21 month old daughter caught a bug and became sick. She was throwing up for about a day and half and had a bit of diarrhea. I became sick too after this. She still breastfeeds and has been wanting a lot of milk though I'm not sure if my production is lower from my own illness. She hasn't thrown up in a few days, but she has only had one very small BM in the last two days and very little urine output compared to her norm. I am concerned about the lack of urine output because she seems to be drinking a fair amount of fluids, between my milk, water with electrolytes and some small amounts of Pedialyte. She no longer has a fever, she has been very hungry, her energy is back... really, her low urine output is the only strange thing. Should I seek medical attention right away for her or will this normalize in a day or two? Is this common following illness in toddlers? She's never really been sick before so I'm just concerned.

Thank you for your help.