you'll get there! swimming is completely unnatural act but one day (and it won't be too long) it will click for you and you wonder why our ancestors ever left the water. keep at it! it will happen

Step 1 - relax! Take a deep breath dude, there are lifeguards at the pool for a reason.
Step 2 - That is a bit much on the training, especially to start. Make sure you are not over training, very easy to fatigue your body and mind, and quickly burn yourself out. Especially, if it is something you are going to struggle with. I see a lot of people stage their swim workouts around time, personally, I think this is a mistake. You don't see a triathlon listed as a "20 Minute swim". If it is possible check the availability of a masters team or group in your area, sometimes they can be expensive, but how much is it worth to you to have a coach there to run your workout and work on your technique?
Step 3 - In regard to your specific problems, there are a few pieces of training equipment out there which may help. Having trouble keeping water out of your nose? Check out a nose plug...
http://www.kastawayswimwear.com/ProductDetail.aspx?id=153
It is relatively unknown that these are legal in competition at the college level, dunno about triathlons though. Also, a lot of people hate them because they take some getting used to but I swear by my snorkel
http://www.kastawayswimwear.com/ProductDetail.aspx?id=1295
I think they are a great way to work on your stroke by eliminating the breathing issue, but they do take some getting used to! (try combining your nose plug and your snorkel, makes life especially easy)
Best of Luck....

Hang in there and don't kill yourself in the water. 3 swims a week with a strong focus on improving technique is much better than 5 - 10 swim workouts a week just trying to get stronger. Swimming is 90% technique and 10% strength and conditioning, so figure out what you can do to work on technique and do that:

- Find a local coach
- Find a local swim conditioning class or Master's group with coaching
- Watch swim videos on Youtube and try to emulate what you're seeing
- Buy a book and DVD like Total Immersion and work through the drills (even though I don't like TI much, it's miles better than just putting in yardage)

On breathing, there's no reason you can't hold your breath in the water and just breathe out before breathing in. This is called expulsive breathing and it's one technique you can use instead of just blowing the air out gradually. If you do this though, you have to blow out forcefully. If you want to try blowing the air out slowly, just hum as you do it. I guarantee that if you hum, you won't get water up your nose, try it! People might look at you funny in the pool, but so what.

As far as being winded, it's because of your technique, I guarantee it. It has nothing to do with conditioning and there's no reason to "hit it hard and often". Find a way to work the technique, and you will be able to swim many many consecutive laps without being winded.

It just clicked for me two weeks ago. I kept repeating that I needed to walk before I ran and that seemed to RELAX me enough to breath right. Also I kept thinking "hey I am not going to sink" and that also helped. I thought I would never get there and I still have a ways to go but keep at it and it will click.

I had some issues with breathing as well, what helped me was practicing just the breathing, sounds weird but it worked for me. In a bathtub at home, or on the side of the pool that you can stand up in would be best. I put my arms in front of me on the edge of the pool in a swim like position and put my face underwater, getting comfortable at first, then simulating face down exhaling rotate to breathe and return to face down. Got my comfort level up. Kind of the like grown up verison of little kids blowing bubbles...
Ironmom's tips and pointers for other people have helped greatly as well. The expulsive, (I call it explosive) breathing is what works best for me. Exhaling during my stroke occurs a little, but I really drain the lungs as my "breathing side" eye comes above the surface of the water. One hard push and its all out and I'm inhaling. Thats what works for me though, don't worry, it will come and when it does it will be an "Ah ha" moment. Good luck!