stomach acidity/bloatedness

Hi im at week 7 now and the morning sickness is getting worse each day. Almost every night i wake up in the middle of the night and feel a strong urge to vomit but i try to push it down with some plain biscuits (cos i really hate vomitting). Recently it has gotten worse. I start to feel acidicity in my stomach and it is very very bloated. Like gastric (i have had gastric problems before pregnancy). I read on some posts that gaviscon works. May i know is it the type that can be easily purchased at watsons guardian? Other than gaviscon, is there any other remedy?