Girls, hello! ? A few days ago I had an ultrasound, my little heart is…

Girls, hello! ? A few days ago I had an ultrasound, my little heart is beating ❤️ BUT there's a cyst of the yolk sac and sometimes there are pains like during menstruation? The doctor said to take care of myself for a couple of weeks and rest more often) What are the risks until what point and how serious is it? I'm very worried, first pregnancy, I really want this baby ?