Problems after Gastroscopy

I am a 47 year old male from the UK, I have had reflux for 20 years controlled by drugs pretty successfully. Recently my normal drug routine 20mg Omeprazole doubling up to 40mg when required was not working and I had several episodes of severe reflux at night and or chronic chest pain (had heart tests but confirmed as reflux). My GP changed me to Lanzoprazole, then a double dose on Lanzoprazole but that was innefective so I went back to GP, he recommended Gastroscopy and I went back onto Omeprazole 40mg daily. Luckily (so I thought) I have private health insurance so arranged for the Gastroscopy. Typical enough prior to the procedure through my daily omeprazole, careful diet and lots of peptic I had got things back under control. I had the Gastroscopy 9 days ago under LA (throat spray) having had one 15 years ago I was confident that although uncomfortable I new what to expect and could manage. The procedure took maybe 3 or 4 minutes but was more uncomfortable than my previous experience, I was gagging throughout, nothing worrying wa found just a couple of polyps, one minor acid erosion scar and mild gastritis. I was discharged after 15 mins or so and the rest of the day was fine, however since the day after the procedure I have had stomach cramps, bloating and chest pain (like severe heartburn or needing to belch and unable, like a lump is tuck basically), I went back to my consultant on day3 and he gave me a very cursory exam and said it was IBS not to worry. Yesterday I saw my GP again as still concerned, he also said probably IBS and just bruising of esophogus due to gagging, he upped my omeprazole for 5 days at 80mg day and also gave Mebeverine for IBS, he said if not better in a week then go back to consultant. I am now regretting having the gastroscopy and worried I have actually made things worse from a point where I was feeling better, my chest is really uncomfortable and 10 days after procedure I am concerned it does not seem to be getting better. I can understand that gagging on the scope can cause trauma but how long should this take to resolve itself. Given the literature advised most people only get a mild sore throat and are fine afterwards I am not at all convinced this is all normal and OK. I am due a monometry test and 24 ph monitoring soon but I am not having anything else until this current discomfort is resolved, the thought of the surgery the consultant is recommending was initially sounding like a solution but now I am really thinking I would have been better leaving all well alone. Can anyone advise if this discomfort is normal following the gastroscopy and how long I can expect it to last.