Since the weekend I've been feeling nauseous, a bit headachy, sometimes slightly dizzy. I figured at first it was just the heat, as I'd been out in the sun quite a bit on Saturday. But I still don't feel right, and it really reminds me of the ms I had earlier in the pregnancy, even down to food making me feel queasy. Is it just the heat, maybe a touch of dehydration? Or can morning sickness come back in later pregnancy? Anyone had similar?