Alright, I\'m injecting some code into another process using the CreateRemoteThread/LoadLibrary \"trick\".
I end up with a thread id, and a process with a DLL of my
You don't have the thread id of a thread in the remote process, because the one you used to load the dll exited when your module was successfully loaded into the address space of your process.
You can easily use the normal interprocess communication methods like named sections/pipes/creating a named window/etc. to communicate with your 'injecting' process.