This is a serious problem, you shall immediately see a qualified physician. it could range from a minor problem to a bigger one so shall be dealt with seriously. there are possibilities of :
1. Acid Peptic Disease
2. GERD: gastro-esophageal-reflux- disease
All these have the maximum possibility in your case, there are a few more diseases, which i think may not be applicable in your case because the complaints are only from last 10 days or so.
A few investigations needs to done comprising of blood counts, Barium meal
X-ray or may be Endocscopy also, but all that would be decided by your doctor. So do not panic and see your doctor, may be a course of antacids will solve your problem.
Wish you a speedy recovery to health
You can also consult Homoeopathy because that is also very effective.