avrdude error/sketches not uploading
I am new to Arduino and electronics and I have a problem that is over my head.
I was able to figure out how to write some sketches and get things to work, so I somewhat understand those basics. I bought a motor shield and lcd shield (both adafruit products). I was able to get both to work using some basic sketches. just recently I was playing around with putting both together and doing some other tests for a project I'm doing. Last night everything worked just great but I tried it today and it didn't work. I decided to try reloading the sketch but it wouldn't let me due to this error:
avrdude: stk500_getsync(): not in sync: resp=0x00
I did my homework and looked everywhere and tried all the solutions (at least the ones I understood).
I correctly have the COM set, the board set, drivers working, etc. I did notice that the reset button no longer resets the board like it did, the lights do not blink (they are on when plugged in). I have tried unplugging all modules and wires but still nothing. I've tried multiple times to upload even the simplest of sketches.
I'm not sure what is wrong and I don't know enough about electronics or programming to know what I've done to ruin it.
Any help would be appreciated. Thanks