Can't cry...help

I don't have depression or anything however I'm normally a very optimistic and full of life girl but after I finished first year and I'm jobless I feel so anxious about my future and I started to worry that I'll become bored cuz there will be nothing to do. Also my my mom who is my BFF left to a different country for work so I need to take care of my little bro and sad...basically I'm the type that repressed my emotions and holds tears back but lately I guess it's cuz of all the changes, I feel the need to cry and there's an aching in my chest but I can't cry...do I feel suddenly feel like crying because i have been holding my tears and emotions inside?