cześć !
There is no problem, at all,
with your employer using HIS commercial licence, for HIS product in question.
Of course. No problem.
As for you — you can go ahead and use your OWN free license, simply for LEARNING / experimenting in your own house.
What could possibly be wrong with that??
Don’t forget you CAN make money with the free version of Unity !!!
Basically, you can make up to US$100,000 a year.
Unity encourages people to make money with the free version - after all there is like 1 million users. (It’s just that you can’t be a “big” (> $100,000) company.)
Simply carefully read all the info here:
http://unity3d.com/unity/faq
(You should realize that it is very likely, that, as soon as you are making money, you will need to buy the Pro version - because it has more features.)
(Also be aware that the copy protection on Unity is essentially perfect - you have to telephone them and so on - so don’t even waste your time trying to hack it.)
Note that if YOU are using YOUR license to make a game for a company, then of course, obviously, you’d be charging them for that. For example if Parker Bros. offers you $20,000 to make some game, but they wanted YOU to supply the Pro licence rights for Unity, obviously you’d ask them for $5000 more to cover that. Anyway, that’s irrelevant where you are now.
BTW …
(A)
“I’m from Poland, we are really poor here” … What the hell man!
Poland is one of the most successful countries in Europe. Try being from Eireland, Greece, Portugal. England is an economic cesspool where only bankers and railroad companies make money. France and Germany are about to implode under mountains of debt. One of the only free, hardworking countries is Poland !
Try raising a family in an expensive city with no economic prospects like Paris or whatever. I think I might move to Poland!
(B)
All skilled programmers, in almost any speciality, can easily make lots of money. It makes no difference at all where in the world you live. Don’t whine! 
Usually when you hire someone or learn about a gifted programmer by reputation you don’t even know where the person lives these days. Surely everyone knows this it’s been true for 10 years.
if you are just starting out, you are in the identical position to someone in a poor third-world collapsing city like Chicago, or a rich futuristic successful city like Shanghai. No problem!
No difference!!! So good luck!!!