No-one can diagnose the problem over the internet unfortunately.
However, I have the same problem :)
I get these bumps (filled with clear fluid) all over my fingers, and I am currently trying to type with a bandaged hand because of it.
Cortizone creams do work to a degree but you have to be very dilligent with them and I have found that even when they seem to clear the problem up, I just have another flare up a month or so later.
I seem to have the most trouble in the middle of summer and the middle of winter...
Middle of summer due to the natural heat... middle of winter due to the fact we have the heater running because it's cold outside..
I have just started trying a cream for Eczema.. it contains Clobetasone Butyrate 0.05% and is available over the counter (no doctors app required)
I have only been using it for 1 day and have seen a small improvement so I will have to keep you posted as to whether it clears it copletely!