today I have borrowed the same refractometer I used at the brewday. Tested it with different sugar water concentrations at different temperatures. The damn thing compensates the temperature, unlike my friend told me.
NOW the calculations to correct the alcohol deviation make sense:
initial brix was 28, 1.115 SG
current brix is 15.2, 1060 SG - Corrected for alcohol, 1.023 (was getting 1006 before)
which makes more sense and gives me a bit of hope.
I think i'll calm down now.