I've been doing deep breathing and anulom Vilom pranayams for about 45 days now, and I'm starting to feel a heaviness in my head, like I'm going to faint, and theres a weird sensation in my cervical area when I do them. My oxygen levels and breath-holding are actually pretty good, but I also notice I have a lot of gas or acidity. I'm a bit concerned about what's happening and would really appreciate any advice on what could be causing this and how I might treat it.