How come?!

Today really in a very weird mood..How come all so many things happen this few days?Really stressed...Very stressed.. Lecturer teach wat also i cant understand..How come like so hard?I wanted to give up studying already..Should i or should i not?I dun know..In such time i got a into a quarrel with friends again..Wat i need is advice and help...But wat i get is actually more troubles...Haizzz...