Diario de TheFatmanNuke, 11 feb. 19

That is totally normal, weight will fluctuate all the time.  

Keep in mind that we gain water weight when doing things like building muscle, eating a lot of sodium etc. I’ve fluctuated 3.6# before! If you start writing these things down you should see a pattern. I gain water if I eat over 3000 mg of sodium. I’ll gain water the day after the gym and it takes me two days to lose it. Your body will probably be different but that gives you an idea. 

The ONLY way you can loose weight directly after exercising is if it is water weight. Don't be so attached to the scale, try to weigh once a week. Any more and you risk altering behaviors that are good because you don't see immediate (and incorrect) results.