How much movement is normal after mounting a TV on partition wall?
You don't say what size or gauge the studs are, but regardless, any reasonable stud is more than adequate for the weights involved. I'm not fully clear on what your connections really are, but in general they sound adequate. Are you sure the bulge occurred during the installation and wasn't always there? Drywall walls are rarely perfectly flat when checked with a straight edge. If the bulge were caused by the installation, it is probably the screws pulling the adjacent stud out of plumb due to some misalignment with the other studs and/or the mounted devices.

Metal studs are rather elastic, it doesn't take much side load for them to deflect a few mm. Despite my uncertainty of what you actually did, I'm fairly sure you have no structural issues and do not need to worry about anything failing.