Yes. Absolutely. I can see where your problem is, because the sound is very small, but it definitely exists.
In perfect pronunciation, it would sound like you are saying 'study-ying'. Even when we speak at normal speed, with more natural pronunciation, though, there is a distinct separation between the sounds 'study' and 'ing'.
A native speaker will know the difference between the words 'studding' and 'studying'. However, depending on the context, it won't matter if you say it incorrectly. For example:
I was at the library all night studding.
The difference is clear to my ears, but it's close enough that I wouldn't care if I heard this. I would know, of course, that the person said 'studding', but I wouldn't care.
The native ear can hear the slightest difference in sounds, just as I'm sure you can in your own language.