Arduino Magnetometer state change - c

Question

I currently have a Arduino connected with magnetometer. When metal is detected it shows a 1 but when there is no metal it is a 0. I currently want a count to detect when there is a change in state but ONLY when it goes from a 0 to 1 not a 11 or 10. I have a last state variable set up to capture the previous state and on the next loop back it compares with the current state. Then from there it will send a "2" to my raspberry pi which I have connected. But for some reason the state detect doesn't work. The last State keeps changing with the current state. Can anyone help check out my code.
/* Intialize Variables */
byte data[32]= {0}; //Data buffer for testing data transfer speeds
int k=0;
float headingdegrees;
boolean VehicleDetected;
float high;
float low;
float Average;
float Sum = 0;
unsigned int Counter = 0; //number of attempted transmissions
unsigned int fail_counter = 0; //number of failed transmissions
unsigned int success_counter = 0; //number of successful transmissions
unsigned long rxTimer; //Counter and timer for keeping track transfer info
unsigned long startTime, stopTime;
bool TX=1,RX=0,role=0;
bool car_detected = 0;
int inPin_on = 4; // pushbutton connected to digital pin 4
int inPin_off = 5;
int val = 0; // variable to store the
int fsrPin = 0; // the FSR and 10K pulldown are connected to a0
int fsrReading; // the analog reading from the FSR resistor divider
int fsrVoltage; // the analog reading converted to voltage
unsigned long fsrResistance; // The voltage converted to resistance, can be very big so make "long"
unsigned long fsrConductance;
long fsrForce; // Finally, the resistance converted to force
unsigned int percentage_Transmission = 100;
const unsigned int reset_counter = 5; //number of transmissions before reset
unsigned int arr_transmission_percentage[reset_counter] = {0};
unsigned int arr_index = 0; //To be used for indexing through percentage array
unsigned int i = 0;
unsigned int temp = 0;
float TxRxAve = 100; //Average Transmission percentage
uint32_t displayTimer = 0;
int changeDetected = 0;
int lastState = 0;
int sendChange = 2;
if ( headingdegrees > high ){
VehicleDetected = 1;
}
else if(headingdegrees < low){
VehicleDetected =1;
}
else{
VehicleDetected = 0;
}
//Detect the state change
delay(100);
if(lastState == 0 && VehicleDetected == 1){
changeDetected = 1;
}
else{
changeDetected = 0;
}
//store the current state
// lastState = VehicleDetected;
/***** Sending Data****/
mesh.update();
// Send to the master node every 5 second
if (millis() - displayTimer >= 5000) {
displayTimer = millis();
//if changeDetected = 1 then send a 2 to the raspberry pi
// Send an 'M' type message containing the current millis()
if (changeDetected == 1){
if (!mesh.write(&sendChange, 'M', sizeof(sendChange))) {
// If a write fails, check connectivity to the mesh network
if ( ! mesh.checkConnection() ) {
//refresh the network address
Serial.println("Renewing Address");
mesh.renewAddress();
} else {
Serial.println("Send fail, Test OK");
}
} else {
Serial.print("Begin \n");
Serial.print("Average:"); Serial.println(Average);
Serial.print("Heading (degrees): "); Serial.println(headingdegrees);
Serial.print("Sending Count: "); Serial.println(sendChange);
Serial.print("Last State: "); Serial.println(lastState);
Serial.print("Change: "); Serial.println(changeDetected);
//Serial.print("Data: ");
//Serial.println(data[0]);
Serial.print("Send OK: "); Serial.println(displayTimer);
Serial.print("End \n\n\n");
;
}
}
//if changeDetected = 0 then simplay send the vehicledDetected
else{
if (!mesh.write(&VehicleDetected, 'M', sizeof(VehicleDetected))) {
// If a write fails, check connectivity to the mesh network
if ( ! mesh.checkConnection() ) {
//refresh the network address
Serial.println("Renewing Address");
mesh.renewAddress();
} else {
Serial.println("Send fail, Test OK");
}
} else {
Serial.print("Begin \n");
Serial.print("Average:"); Serial.println(Average);
Serial.print("Heading (degrees): "); Serial.println(headingdegrees);
Serial.print("Vehicle Detected:"); Serial.println(VehicleDetected);
Serial.print("Last State: "); Serial.println(lastState);
Serial.print("Change: "); Serial.println(changeDetected);
//Serial.print("Data: ");
//Serial.println(data[0]);
Serial.print("Send OK: "); Serial.println(displayTimer);
Serial.print("End \n\n\n");
;
}
}
}
while (network.available()) {
RF24NetworkHeader header;
payload_t payload;
network.read(header, &payload, sizeof(payload));
Serial.print("Received packet #");
Serial.print(payload.counter);
Serial.print(" at ");
Serial.println(payload.ms);
delay(500);
}
lastState = VehicleDetected;
}