My car was smoking and now it wont start?

Hello guys, I have a few questions about my car. It's a 2005 Chevy Cobalt LS and I've had it for only 1 month.

When I bought it, the only thing the Chevy dealer said was that they recommend struts and shocks within the next few months but they said everything under the hood was great.

When I started driving it, I was just learning how to drive a 5 speed Manuel transmission car, and it took about 5 days for me to get the hang of it. I broke hard a few times and I started hearing a clinking noise whenever I pressed down hard on my brakes, so I thought it was just because I wore out the break pads a little. While also learning how to drive stick, there were a few times when I think I was burning oil when I didn't switch gears at the correct time. So in total, the only problems I ever experienced in the last month with my car was the clinking brakes and the once in a while smell of burning oil.

Then 2 days ago, for the first time, I heard a strange clicking noise every time I accelerated my car in 1st, 2nd and 3rd gear. It kind of sounded like a pen being held into a fan and the fan blades smacking the pen. I drove my car around for one day, probably a total of 200 miles and then I didn't drive my car the next day.

Today I was driving my car on the freeway and I got stuck in traffic for an hour. A dead stop and go, stop and go kind of traffic, where my foot was constantly on the clutch, gas and brakes. Finally once I got out of the traffic I started trying to accelerate to get my car from going under 10 mph to freeway speed. At first I noticed that once my car reached 60mph, it stopped accelerating, even with my foot on the gas firmly and the gear was in 5th.

I dropped my gear down to 4th, tried to accelerate, then popped my car back into 5th and it slowly reached 70mph. I was only driving 70 for about 1 minute before I heard and felt a pop. Immediately I checked my rearview mirror and I noticed thick white smoke coming from my car, so I pulled over and we seen thick white smoke coming out from the hood of my car rapidly. We popped the hood and checked and there was oil leaking onto the floor and the smoke wouldn't stop flowing.

My fiance checked the oil and she said it seems like the water and oil mixed. When we asked a family member their opinion, they said it sounds like a blown head gasket and that means my engine is ruined.

I just need some more opinions. Does anyone know what may have happened? Any opinions or advice? Any ideas of how much it would cost to fix it? Would it be best to fix this or get a different car? Thanks everyone!