This was my problem for a very long time... I knew that I could not know everything but I still struggled to know everything while cursing myself for not knowing everything especially when am learning a new framework or technology and this usually leaves me with a very fast pulse making everything look impossible in my head and it would stop me from learning any further for that moment. Truly most people can't get out from this rollercoaster until they know and accept this. I was an example of that.