I need help with singing... (!)

I am trying to learn, because I want to a lot, so I do songs that express stuff this way with words as well, not just writing music all the time… =P
But I’ve been having issues, if anybody can help… =S
Firstly I’m very shy (i got somewhere, I can now kind of do things in front of myself =P ), so what are good ways to stay relaxed? It starts to get kinda strangulated. =P
Also, how can I try to get more power, without getting too tense?
And, I was reading about breathe control n’ all, but find it hard to do this, without getting tense (again) =P I end up breathing too much, it’s not good…
Thankyou =)

If it matters, i do ze alto stuff, but can’t get all they way to the top of that

ps. i have no money to pay people to teach me..! =)