Dear mother, first of all you are doing a great job as an exclusive pumping mom.
Your baby's weight gain is excellent - birth weight 2.6 kg to 5.2 kg at 3 months means she has doubled her birth weight, which is exactly expected at this age. So growth is on track.
At 3 months, what you are describing - taking very less milk, getting distracted very easily, and hard time sleeping - is very common and mostly developmental:
1. 3-Month Distracted Feeding: At this age babies become very aware of surroundings. They look around, get distracted, pull away from bottle/breast. Feeding amount may appear less in daytime but they compensate at night.
2. 3-Month Sleep Regression: Sleep pattern changes around 3-4 months. Day-night confusion reduces and babies start having more frequent night waking.
3. If baby is active, playful, passing urine 6-7 times, gaining weight, and achieving milestones like social smile, cooing, head control, then this is likely a normal phase and not due to any illness.
Other causes to rule out are nasal block, mouth thrush, ear pain, teething discomfort, or change in milk flow from bottle nipple.
Next Steps
1. Continue weight monitoring with your pediatrician - plot on growth chart.
2. Try feeding in a quiet, dim, low-distraction room with no TV/mobile.
3. Follow baby's hunger cues rather than fixed schedule. Offer small frequent feeds.
4. Check bottle nipple size - at 3 months flow may need to be changed as per baby's comfort, too slow flow can cause frustration.
5. If baby has fever, vomiting, loose stools, less urine, continuous crying, or poor weight gain, consult pediatrician immediately.
Health Tips
This distracted phase is temporary and usually improves in few weeks. Maintain consistent sleep routine - warm bath, dim light, gentle rocking at same time daily. Avoid forcing feed. Burp well after feeds. Take care of your own hydration and rest as exclusive pumping is demanding. Do not start solids, water or formula without pediatrician advice before 6 months