Could My Fatigue Be Vitamin B12 Deficiency From GERD

I have reflux but do not take Prilosec or any other similar med. Sometimes I take Zantac or chew up a Tums. My question is-can having reflux affect B12 absorption? I'm always tired and have real bad digestion (takes forever for me to digest anything and always constipated. Have had one blood test after another at various doctors and they all tell me they don't see anything of concern. They have never tested me for B12 levels or iron. I barely eat red meat, sometimes eat chicken and fish, not much dairy, I switched to egg whites, no milk, and my cholesterol is high. just wondering if there's any connection at all.