Practicing English day4

Today, I had two classes. 
public finance and law.
When I opened my bag, I realized that I forgot my textbook.
I was bummed out.
And my law teacher was speaking too slow.
I almost fell asleep, more then once
Today was not my day
It Sucked

Very good, but just some minor changes are needed to make it more natural sounding, regardless it made perfect sense to me. 

Practicing English day4

Today,I had two classes
public finance and law.
When I opened my bag,I realized that I forgot my textbook.
I was bummed out. (fragment)
And my law teacher's speech was too slowly.
I was about to take a nap many times.
It's not my day
Suck

Today I had two classes in public finance and law. When i got to class, I open my bag and I realized I had forgot my textbook. To add on to that my law teacher's speech was so slow. I was about to fall to sleep, it was so boring. Today was not my day, it sucked.

Practising English day 4

Today I had two classes: Public Finance and Law.
When I opened my bag, I realised that I had forgoten my textbook.
I was bummed out.
Plus, my law teacher's speech was too slow for me.
I nearly nodded off several times.
It's not my day.
This sucks.

Practicing English Day 4

Today,I had two classes. (Sounds more natural to say, "I had two classes today")
Public finance and law.
When I opened my bag, I realized that I had forgotten my textbook.
I was bummed out.
And my law teacher's speech was also slow.
I was about to fall asleep many times.
It's not my day.
Suck (It sucks.)

Pretty good. Hopefully your day would be better tomorrow!