Pain between the scapulae that worsens with sneezing (10/10 intensity) and has persisted since Holi suggests a musculoskeletal origin, potentially involving: paraspinal muscle strain or myofascial trigger points over the thoracic region or even nerve irritation.
Next Steps
Consult a Physiotherapist for better recovery.
Physiotherapy focused on manual therapy, posture correction, pain relief, and gentle mobility should be started ASAP.
Ultrasound Therapy or TENS should be helpful, according to the dosimetry decided by the Physiotherapist.
Health Tips
If you have pain at rest that wakes you from sleep, Unexplained weight loss or fever, Radiating pain, numbness, tingling in arms or chest.. you should consult a Physician at the earliest as these would be red flags for any regular muscular complaint.