Couple of quick HC-06 bluetooth questions

Using Arduino Networking, Protocols, and Devices
2

  1. The short answer is "yes", but why don't you serial.print(data). It will probably lead to less surprises.

  2. It isn't. The baud rate is only relevant to Arduino<>Bluetooth comms, and it isn't negotiated. You decree it. Further, any connection at 38400 is very suss, and probably didn't happen.

  3. No. But it does sound rather like you don't know what you are doing, and the absence of code doesn't help in this matter. At a guess, you are simply not reading the input correctly.

You might find the following background notes useful.

http://homepages.ihug.com.au/~npyner/Arduino/GUIDE_2BT.pdf
http://homepages.ihug.com.au/~npyner/Arduino/BT_2_WAY.ino

and

http://forum.arduino.cc/index.php?topic=396450.0

If you truly have one-way traffic, things can't be serious.