Training for my 1st Triathalon - Need some Advice!!

Hello everyone, this site is great. I have just begun training for my first triathalon and have learned a ton from this site.

 I started training two months ago for a tri that is on July 26th and wanted to get some advice on the training schedule. I started training because I've done nothing the last 4 years and just put on too much weight. I've always played sports growing up but i'm totally new to the tri stuff. I have a bike so i'm ready to go.

 For the last month and a half I've been working out six days a week. The first month my workout looked like this:

Monday & Thursday: Swim 350 yards & Run 30 minutes

Tuesday & Friday: Swim 350 yards & Bike 13 miles

Wednesdays: (Our long day) Swim 400 yards and Run 40 minutes (The 40 minute run really stretched me out)

Saturday: Bike 5 miles

Sunday: Rest

For the last two weeks I have followed the same schedule, but i have increased everything. My normal swim is 500 yards, normal run is 40 minutes, and my bike is 15 miles. My long day is 600 yard swim and 45-48 minute run. Last week I did a 26 mile bike, it took alot out of me, but i made it.

Here's my question, with a few weeks to go, what do i need to do to get ready but not tear up my body, as i did with the 26 mile ride. I'm a big guy (6', 270lb) , but i work hard and sometimes i feel like i overdue it. Which is fine, but i just want to finish the race. I have not tried the bike, plus the run yet, but I'm thinking i need to do that before the race. If so, what type of distances on both should i try.

 The race will be a 350 swim, 13 mile bike and 3.1 run. Do you train right through the day of the race or do you allow a little off time? Thanks in advance for the help!!!