learning Portuguese: basic greetings and confusing numbers

Why is language learning so stinkin' hard?! Well, as suspected...my background in Spanish has been helfpul in understanding what is being said, but so far it hasn't helped much in my learning to speak Portuguese as I just get more confused about which is the correct way to say things and have to pause before speaking to make sure I am planning to use the correct language.

Q: How are you?
Portuguese: Como estas? pronounced esh-ta-sh.
Spanish: Como estas? pronounces es-ta-s

Typically this is said informally as "Tu te bem?"

A: I am fine.
Portuguese: Estoy bem. Pronounced esh-toy.
Spanish: Esta bien. Pronounced like it looks.

Seems pretty easy so far, right? To give this simple answer takes me waaaaay too long! Why? Because of the whole process that has to go on in my head....WARNING: you may not want to read further as you are about to enter the abyss of my brain, and it can be scary in there!

Here's the basic process: 
What did they just say?....Ahh, they said how are you....okay, how do I answer? In Spanish it would be....so that means in Portuguese I need to use the "sh" sound....alright, here it goes....

By the time I get an answer to come out of my mouth, the poor person who asked the question has had to wait an eternity for an answer to something that is just a social greeting anyway. Sheeesh!

I am also having trouble with numbers (again). I had a struggle with numbers when attempting to learn Khmer. The other day I had a colleague laughing at me as I stuggled with the difference between two, ten and twelve...you must pronounce these out loud to hear the similarities. NOTE: I did not have them written in front of me when the problem occurred, it was an auditory only exercise (until later when she wrote them down to help a poor girl out).

Two - dois
Ten - dez
Twelve - doze

Hopefully I've got it now until the next time I am at the store and can't understand what the cashier is asking me.

Imagine what your life would be like if your daily tasks took this much effort? It's exhausting I tell you. Exhausting!