Hi Khmaies, thank you for sharing. This has started with programming things only? Because studying programming only does not stick in mind. It requires implementing things, reusing them daily, etc. As much as it seems simple concepts, they are very abstract and it 's obvious only after you get some expertise. I remember myself at first programming class and the teacher drawing an array and explainning to me how it works, it wasn't obvious to me. I didn't pass. It was long years struggling in this area, before even starting working, only on classes. This affect yourself confidence, making you questioning yourself. Being interviewed brings a lot of stress also. I would suggest first you believe you are healthy and keep studying, coding, then, of course, if you think you really have a memory issue, try to look for a doctor.