What Causes Swallowing Difficulty?

Hi. Thank you for being available to answer my question(s). I have just begun having difficulty swallowing, almost like I ve forgotten how to swallow, which immediately makes me start to choke on whatever food and or drink I have in my mouth... I m getting to where I don t want to eat and have to go extremely slowly and almost puree the food in my mouth. But sometimes even my own saliva is hard to swallow. Do you know what causes that? It s a bit frightening and making me panic a bit. I have had several episodes where the food slides past and or keeps me from swallowing. I m starting to get very concerned. Can you help?