Why do I feel emo easily recently?

i think failing a unit last sem is the main reason to demoralize me.
when i thought uni student should be enjoying their life without considering much on their study before they graduate and go to work like a dog everyday, i was proved wrong when i failed a unit last sem.
that guilty feeling is growing bigger when time passed instead of disappearing. guilty of making my parents pay another 4k while the tuition fee is already a hefty 33k annually. guilty of not doing my best in the finals when they actually thought that i worked hard on it. no, i did not gave in my best effort when doing the final exam. i doubt i can put on 100% effort on this sem's either.
while i always dream of studying abroad since i was a kid, the plan just didn't go well as the wealth of my family couldn't support me to go study abroad and there is this chance that i can go study in Australia for a relatively lower cost which i believe my parents are more capable of sending me there, but i think i will kinda screw it up as it requires some results which i did not achieved it. although it is just a 0.75 difference but really that was a shame as this is suppose to be easy for other people.
suddenly i see darkness ahead of my life. there are more uncertainties to come. i am not confident enough to overcome all those. i feel weak. no doubt that i changes a lot this year. i wouldn't have thought of all those stresses come to me when i was in first year. now i am only in second year , i still have 2 years to go.
damn! while people tends to say working is far more stressful than studying, i can't even think of what will i become after i graduate and eventually is at work.
gosh i need motivations and the most important of all, concentration.