Every time a blade is used, a tiny layer of skin is removed. The body produces replacement scar tissue. An electric shaver does not cause the body to do this. So two or three weeks are needed for the skin to adjust. Therefore when changing from blade to electric, or even from one electric shaver to another, persevere at least for a couple of weeks before making a final decision as to whether you want to continue.
Most manufacturers recommend new heads after one year.
Some can go for 18 months or even two years.