Does Nitrofurantoin For UTI Has Any Side Effects?

I have been taking Nitrofurantoin for a severe UTI which had me in hospital for 5 days. I finished the course yesterday, although I didn't feel like eating yesterday evening (I did take my last tablet), I have been sick this morning and feel terrible. Is this likely to be a side effect and how long is it likely to last. I am a 75 year old woman.