Has anyone had this happen (postpartum question)

Since starting my period back postpartum - started in December - my periods have been much longer than they normally are (I’ve always been super regular 24 day cycles). Since starting back they’ve been 30 days on the dot each time - now 5 periods later and I have my first 24 day period and I have felt SICK since starting my period. Hot flashes, nausea, stomach pain, actually puking at one point. I am NOT pregnant and for sure have started my period. Is this just a coincidence and maybe I’m sick or could it be a hormonal shift and my periods going back to my normal. What can I take for this nausea cause I’m dying.