How did I use so much data in a day?

I literally picked up my new iphone from the store yesterday, and I've already used 0.7GB/4GB. How is that possible? Is it because of how many apps I've downloaded, because that's nearly a gig in a day, and it doesn't seem quite right.

Do iMessages show up as texts?

So my parents are really strict, and don't want me going over 1, 000 texts a month so that I can 'focus more on school'. Anyways we have an unlimited plan, they just check the bill every month to make sure I don't go over 1, 000. Considering I'm a teenager that's really difficult. I text like the same 3 people everyday (all 3 have iPhones) and I'm pretty sure we've sent thousands and thousands of messages to eachother.
Since its iPhone to iPhone, will they show up as like a million texts? Or data? Please let me know. I went overboard with my texting this month and I don't want to get in trouble!

Supernatural season 7 on Netflix dosen't work?

Well when I turn on an episode of season 7 the sound is messed up you can't hear them talk season 1-6 work fine so I just want to know why P. S.I've tried watching it on wii, iPhone, and PC

How to share my laptop internet with my iphone 4?

My laptop is using Wi-Fi internet so i want to sync my iphone to my laptop in
order to use that Wi-Fi connection.

I can't connect my iphone directly to the router for very long as i keep losing signal as the router is quite far away however my laptop has no problem

What carrier is my iphone locked to?

My cousin updated his iphone to ios 6 and now the iphone is locked. He said that the phone was a gift from his uncle and his uncle bought it from an apple retail store (that's what he says).

From what i know, all iphones that are bought at apple are all factory unlocked therefore it's not possible for it to be locked after updating. So the only explanation left is that his uncle bought the phone from a carrier, and so the phone is locked.

What do you think? Is there any other explanation to that? And how do i find out what carrier is the phone locked to?

Added (1). His uncle said that it was bought from an apple store