i'm (I'm) really tired,sleepy and sad (you wouldn't say tired and sleepy in the same sentence. Essentially, they mean the same thing. So say  "I'm really tired and sad."

it's (It's) 4:30 a.m,(Change to semi-colon). i (I) didn't sleep until now,(change to period). i(I) had many works to do (I had a lot of work to do) ,(Take out this comma. It's not necessary.) and i(I) had to study Turkish,(Make this comma a period and start a new sentence.) the(The) saddest thing was losing Argentina vs(change to "losing to) Germany by Gotze's goal

so(Don't start sentences with "so." You can use "therefore" instead.) i'm so tired,sleepy and sad(addressed in the first sentence.)

Completely corrected your entry should say:

I'm really tired and sad. It's 4:30 a.m; I didn't sleep until now. I had a lot of work to do and I had to study Turkish. The saddest thing was Argentina losing to Germany by Gotze's goal. Therefore, I'm so tired and sad.

Every time you're referring to yourself, you need to capitalize "I." Also, make sure you capitalize a new sentence. Put a space after your commas (,). 
:)