Tamoxifen producing painful windy stomach?

Am new here.

Has anybody had similar indigestion whilst taking tamoxifen.?..

Suffered cancer in breast, lumpectomy, and lymph node clearance a year later

Taking tamoxifen for a month, changed over after a year of Letrozol as I kept looking at the alendronic acid and not taking it, and already had osteoporosis.

I have painful indigestion and stuck sensation in stomach.

GP giving me antacid liquid and omeprozol

I lot less nauseous than when I was taking letrozol. But now horrible stuck pain. Not sure what's what!