Worst period symptoms ever !

When I first got my period when I was around 13 I never experienced symptoms, no cramps, no fatigue, sore boobs nothing. Anyways, now I’m 20, recently became sexually active in the last few months and since then my periods have been horrible ! I get extremely nauseous, have the worst hot flashes, cramps, and I bleed much heavier. The only thing that’s changed that I like is that my period is now only 3-4 days but when I was younger it usually lasted a full week. Has this happened to anyone ? What do y’all ladies do to help with bad period symptoms? It’s really bothering me because it effects my day to day activities. Especially being a college student I can’t deal with the nausea during class and most definitely not the hot flashes.