I cant handle stress

I am just venting here because it seems like I just cant relax this past week.

I am a full time student and working full time as a sales woman. This past week I started on my final presentations for school (I do online) and also my grandfather was put into the hospital due to falling. My stress level is so high I believe it is unhealthy. I feel like my heart is going to explode. When it comes to work I have to be happy on the inside and on the outside because customers can sense when you're at your weakest. I took off yesterday for a mental health day and ended up sleeping half the day so the things I wanted to get done didnt. I know it is my own fault but I really needed sleep. I feel like I may be so stressed because my period is coming tomorrow and my hormones are all out of whack. I just feel so helpless and out of control. I just need a break😭