Check that blue filament guide that you made if you can feel a bit resistance when you manually pull the filament. In time the filament will rub that guide to the point that It will start to form a hole in a V shape. If it comes to the ex cruder change it sooner as you can. It's a cheap "upgrade" if I can call it. For me it's not normal to upgrade stuff just to make it work as it should. But this is ender 3 so you will get alot of that.
But if it comes to your temperature problem I don't know. It may be related as with big enough temperature differences you may get blobs stuck in your hot end