True?

My mom used to not let me eat anything cold on my period. Like on really hot days everyone would get a big ice cream cone except me and for some reason I just want to crawl in a hole and cry. I wouldn't get any cold drinks or food and when I asked her why she said it would make ur period be at least 3 days longer and give u terrible cramps. I asked my friends and they all said it's not true so I really need to know if these symptoms are happening to anyone else.