scare to upgrade

Hello, i have 1 moth my website now.
But i'm scared to upgrade from 7.1.1  to 7.1.3 (newest)

What must i look to do it right? What can be wrong?

Better to let it do, but it's gonna cost me so much to pay someone to do it each time.

Also, the plug-ins.. what if they don't work....

ANd must i do first 7.1.1 to 7.1.2 and then 7.1.2 to 7.1.3?

So much questions :-) 

You should be fine as long as you have not edited major core files. If you at 7.1.1 odds are you will be fine.

As we always tell members, if your not sure you need to learn how to clone your site in a subdomain/folder and duplicate database under different name, change info in the header.inc.php in the cloned site to match the database name and the folder where you have placed the clone.

I have posted how to do this before.

If you first backup your site files COMPLETELY, everything including files that have been uploaded such as photos and videos, etc. and do a complete backup of your database, then if something does go wrong, you can simply restore your site back to the way it was.

However, I would do as Newton advised, still have those backups which you use to clone your site; the clone site must have the header include file change to reflect the clone site and database.  Search the forums for how to do this.