I took tums with my first pregnancy and it helped, I didn't have acid reflex till the end of my pregnancy as well, and I'm 16/17 weeks now and I hope I don't have acid reflex this time!! I couldn't stand it! Also drink water too, and tums, it helps almost immediately, or well it did for me
Eating smaller meals more regularly was helpful for me- also making sure to drink plenty of water in between meals. Tums and milk were helpful as well. Feel better!
I have ranitidine tablets which I think are like zantac, I'm careful what I eat, just eat little and often and have a glass of milk to ease it now and again. Also found not lying flat helps, prop myself up a bit