Bad craft day

Somethings has been gone wrong with me on last weekend, I can't craft well. Look at the house shape coaster that I crocheted, so badly shape and the tension is all hair wired, very ugly. Can't believe I am the one who crocheted it. Where does it went wrong? Am I using the wrong size of crochet hook that making the gauge to be loose? Maybe I'm not concentrate myself enough while I was crochet on that time. This coaster really need to go to the trash, poor coaster....I'll not giving up trying to crochet another coaster, this time I'll use a smaller size of crochet hook instead of what has been stated in the pattern book. Hopefully it'll turn out correct this time, will post it later once I finished crocheted a new one.

Look at the bottom of the coaster, the tension is out making the bottom way out bigger and ugly.