scientific insomnia

For whomever interested in my work I leave this mere idea of the ultimate solution to all energy problems that may face humanity in the present and near future, if my idea is solid then I have laid my hands on the greatest discovery anyone in my position could wish for.
My idea is very simple, with regards to the work of Einstein and his theory of relativity, I am only interested in his interpretations of the Energy and Mass interchangeability, in essence he proved that the speed of light can never be achieved, but here lies my theory, in practice when a particle is accelerated to near the speed of light, say 99.997% of the speed of light, at some point it stop accelerating and starts swelling, meaning its mass starts to increase, here lies my first question, where exactly does the swelling starts, at what speed exactly does that start to happen. NOTE 1
Now imagine with me this hypothetical idea, the particle in question starts accelerating, as its velocity starts to rise up its Energy increases ( E=mv2), so far the m has the same value nothing has changed, now let’s pump up the juice and give the particle maximum power and let it fly as fast as it can, it will start gaining speed till it get, theoretically as close as possible to the speed of light, which is a point that needs to be determined NOTE2, Now what we I will address as this fantasy like equation
(e=(mc2)-d)
E = Energy, M = Mass, C = speed of light (299,792,458 m/s)( ≈ 186,000 Mi/s)
D = the to be determined Value that will make up for the difference between the utmost value for E and the exact point when power becomes the swelling of the particle, that’s the exact point Energy becomes Mass, of course it keeps going afterwards but at that exact moment, or point in time, with the exact values, we know that
(e=c2-d)
So still again theoretically and I am pretty sure I might be 100% wrong in everything I am saying, a particle weighing 1 unit, may that be grams or a much small unit of mass accelerated to Just before the speed it starts to swell, we calculate or check its velocity at this stage or point in time, say its 185,997 miles per second
(d=c2-e) and since we already know that e=mv2 then (d=c2-(mv2)
I wish this could be tested somehow, I wish to know more about this subject to further understand what am I up against, if (d) is something that can be determined then it could help me understand more about the swelling of the matter, why does it happen, and rather answer my ultimate question, can the swelling be reversed, not avoided but reversed if more energy after reaching (d) point is resulted in pure Mass then in basic sense, this could be reversed so decreasing the mass somehow can result in energy extraction …. Somehow.
It sounds crazy, sounds like it could never work or rather very dreamy and unscientific, that’s why I should read more about it and hopefully I will find an answer soon.