Welcome to HCM.
bloating,pain is most likely due to excessive gas formation after indigestion
to subside it.
Take nsaid/muscle relaxant
to subside back pain
but take it with some food,milk and continue above medicine .
B12,calcium,d3,vitamin supplement will be helpful at this age.
Apply nsaid gel locally.
Start exercise,yoga regularly.
Drink more water and fruit juices,vegetable soups,buttermilk.
X-ray lumber region is necessary to ruler out cause of back pain.
Also go for cbc,fbs,ppbs,urine,b12,calcium,thyroid profile.
Consult your physician for better guidance and proper medical management.