Yeah, that is fine. The barrel tilts because it is unlocked; it tilts back down when it goes back into battery. Just make sure you never force the weapon back together, sometimes it is possible to get the slide on funky and misaligned.
I highly recommend looking on youtube for disassembly videos, there is also some Glock site, can't remember which, that had a good video too. There is at least one really good one I saw that will go through total disassembly, which at some point, if you are like me, you will just have to do. The Glock is different than other pistols, total disassembly is easy with just a punch, but some of the processes can be "mysterious" if you don't understand how it is made. You will also gain more appreciation for the engineering that went into it and become more familiar with the weapon as a whole.
You will never have to go past field stripping normally, but it is nice to know how. Also, learn WHERE to put the oil or grease --they actually work better if put sparingly in just the right places, as opposed to all over like you would with other weapons. The Glock will run better with most parts dry, dirt and debris won't stick to it as easily.