Alright. So after chatting with Sarah, she diagnosed my problem to be plugin conflict.
The screenshot shows how the plugin looks like when i activate Woocommerce and SEO by Yoast.
OK, let me elaborate the problems.
1 As you can see, some of the icons are missing. last time when i refreshed the coupon page, the Facebook icon wasn't shown up. Now, it was another icon not showing up.
2 After i've twitted, the number is not adding up, it will always remain at ZERO.
3 See that red ! triangle below Google+ button, that's what happened after clicking on Google+ icon.