If this is the first time she has developed pain abdomen (i.e. no similar pain abdomen before one week) along with an associated difficulty in breathing I suggest you to visit Emergency Department of Bir Hospital/TUTH Teaching Hospital or other big private hospitals for further evaluation.

she is 48 yrs old and encountering this problem since 6 days, and she is having difficulty in breathing as well.

Hi Manisha Ji, other relevant information like your mum's age and duration of her problems would have been helpful. 3 mm flesh(Polyp) in Gallbladder is less likely to cause her symptoms. I recommend to perform basic blood tests and an Upper Gastrointestinal Endoscopy to look for Ulcer in Stomach and initial portion of small intestine because ulcer is common cause for pain abdomen that worsens after meal.