Developing Your Psi Energy.., Should it start off this tiring? Options

I've been running the regular meditation and practices for developing your psi energy as described on some sites shown here. Visualising a sphere behind my abdomen, pulling the energy up through my chest, and to my hands, ect. But what I have noticed recently is being completely exhausted the day after. I've been keeping a routine of 30 mins on day, none the next, and repeat. Today I could barely lift my backpack. I haven't been doing much out of the ordinary other than extending my time from 10 to 30 mins. Perhaps I'm rushing it abit? I'm just curious to know if anyone else has had these effects on them.

Hi all, I have to say I also feel tired , but somewhere I read that if trying to raise energy as you / we are, using your own energy you are bound to feel tired, where as if you draw in the energy from outside you IE the earth or just draw in from the universe using pore breathing etc, you will not feel tired, maybe some one with the experience can put me right.

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