So far, I've only used ATTiny... but doesn't the LCD need 5v logic levels? Relay needs a driver. What's you power source? Regulated? Decoupling capacitor? Got a diode across the relay? A schematic of your circuit would have answered all these questions and more.
I usually simulate a circuit on the computer before I build, but my program doesn't do MCUs, so I do a quick sloppy sketch to keep my pins straight while wiring it up on the breadboard. I've gotten help here just off a scan of the sketch, and many times from poor digital photos.
The LCD may not be intialized proper, wrong clock or delays. Contrast might not be set, backlight... You most understand that without pictures, and very few details, its tough to visualize what you have done, and to see what went wrong.