Going to switch from PS4 to PC and would like my username to be consistent. when i try to use the username i have on PS4 it says unavailable

If it is not shared it's just taken I suppose, however I do have another idea that i would like to be settled either way. So I tried the beta on pc way back using my hotmail email, and I recall using the username rjthebarbarian. I may have forgotten my password and "reactivated" the beta a second time for something and changed the username. I don't recall using the PC to ps4 transfer. Though my username on the PS4 is rjthebarbarian, I'm assuming it's just because my psn is rjthebarbarian

So did i screw myself out of having the username I want for PC