My best beers have been wheat beers. I seem to have had the best success with either the wheat dry malt extract, or regulat wheat malt extract. I had that fizz problem when I used too much corn sugar when I capped the bottles. It also tasted a little sugary. I used less than a half of a cup the next time and it wasn't so bad. On my very best batch, I used dry malt extract (wheat flavored) for bottling and it was perfect. No more corn sugar for me. I started finishing in 5 gallon pop kegs until we moved out of California and I had to sell everything. My best batch was a combination of 52 highly carbonated bottles, opened and poured into and mixed with a batch that didn't carbonate at all in the 5 gallon pop keg secondary fermenter. I must have lost the seal somehow, but it was 10 gallons of the best tasting wheat beer I ever made. Served it at a Christmas party and it was a huge hit.
Best guess for you is don't use so much corn sugar. There are tons of web pages out there dedicated to homebrewing. One or 2 experts lurk this board as well. Keep it up and don't be afraid to make mistakes. We all do. That's what makes us better at it.