After the sleeve you may need to close some scarring area and produce symptoms such as these. This surgery also cause reflux symptoms. Other possibility could be an active gastritis, helicobacter pylori or gastro esophageal reflux.
At this time, these symptoms should not be present. Possibly some changes are important feeding, use of medications that reduce gastric juices and others that make emptied faster.
The most important thing now is to contact your surgeon to find out why this is happening.
You'll be better if you attend your physician