2004 Toyota Sienna rear brake sensor

After changing a brake lamp I realized taht I now have no brake lights at all. Also the transmission will not engage out of park without extra force. I believe there is a connection between the brake pedal and the rear lights that has been disrupted somehow.
would this cause this to trigger a lock on the transmission and are the two problems possibly related due to an electrical malfunction? Is this something I can trace or does this need to go to the dealer?