when I started training about 2 months ago I was using less weight but I felt more pumped up in the end I mean I could feel my muscles strained and bigger at the end, even several people noticed the difference I had even in the first two weeks.

but gradually as I have increased the weight I am picking I dont get the same pumped up feeling anymore.instead my muscles are just tired in the end.should I go back to lesser weights or is it all in my head?