Hi. If you normally have acid reflux disease, it tends to increase in pregnancy dur to hormonal changes. As such , it will not harm the baby, but because of vomiting or decreasd intake, it will effect your wt. gain and hence of the baby as well. Eat a bland diet and small and frequent meals. Take moe of cold milk, jelly, curd fruit custard, etc. The reason for red/brown liquid is due straining while vomiting or reflux, which causes minor oesophageal tears. Take the help of a gastro-enterologist, if not settled. Also make the head end of your bed slightly raised and don t lie down immediately after eating. Thanks.