Unity:Detecting collision switch while maintaining game functionality - unity3d

Question

I have created a random generator for a prefab called "Tunnel". Whenever i collide with a tunnel prefab, i wish to keep the game running. If i am no longer colliding with a tunnel i wish the game to stop.
The game works fine for the first tunnel, but when i reach the end of the first tunnel (start of the second - they overlap), my "OnTriggerExit2D" function stops the game.
Is there a way to tell my "OnTriggerExit2D" to check if i'm colliding with a different tunnel?
Here's my code:
void OnTriggerEnter2D(Collider2D other)
{
Debug.Log (other.gameObject.tag);
if (other.gameObject.CompareTag ("LeftTunnel")) {
touchRef.onTunnelL = true;
}
if (other.gameObject.CompareTag ("RightTunnel")) {
touchRef.onTunnelR = true;
}
}
void OnTriggerExit2D(Collider2D other)
{
if(other.gameObject.CompareTag("LeftTunnel"))
{
touchRef.OnTriggerExit2Dchild();
touchRef.onTunnelL = false;
}
if(other.gameObject.CompareTag("RightTunnel"))
{
touchRef.OnTriggerExit2Dchild();
touchRef.onTunnelR = false;
}
}
thanks!

Answer 1

So, after consulting with some people I decided to change the whole mechanism to work with ray casting and it works great now.
Here's the code for anyone in the future (I call cast function on Update):
void Cast()
{
for (int i = 0; i < Input.touchCount; ++i)
{
Vector2 test = Camera.main.ScreenToWorldPoint(Input.GetTouch(i).position);
RaycastHit2D hit = Physics2D.Raycast(test, (Input.GetTouch(i).position));
Vector2 touchPos = new Vector2(test.x, test.y);
onLeft(touchPos);
onRight(touchPos);
}
}
void onLeft(Vector2 touchPos){
Collider2D tempL;
if (tempL = Physics2D.OverlapPoint (touchPos)) {
if(tempL.CompareTag("LeftTunnel")){
Debug.Log ("Hit Left tunnel");
onTunnelL = true;
}
}
else{
onTunnelL = false;
}
}
void onRight(Vector2 touchPos){
Collider2D tempR;
if (tempR = Physics2D.OverlapPoint (touchPos)) {
if(tempR.CompareTag("RightTunnel")){
Debug.Log ("Hit Right tunnel");
onTunnelR = true;
}
}
else{
onTunnelR = false;
}
}