How to check if your character is falling 2D - C#

Hello, just come to ask if anyone knows how to check to see if my GameObject (character) is falling?

using UnityEngine;
using System.Collections;

public class Movement : MonoBehaviour {

	public float speed = 6.0f;

	public float jumpSpeed = 20f;

	bool grounded, interact; //bool for checking if player is grounded so they can jump, and bool for interact, so that player can only interact when in range of thing to interact with

	public Transform jumpCheck, interactCheck; //transform variable for the end points of the linecasts

	RaycastHit2D interacted; //a variable type that stores a collider that was hit during linecast

	float jumpTime, jumpDelay = .5f; //jumpTime = 0 by default

	bool jumped;


	Animator anim;

	void Start()
	{
		anim = GetComponent<Animator> ();
	}

	void Update()
	{
		PlayerController ();
		RaycastStuff(); //call the function every frame
	}
	
	void RaycastStuff()
	{
		//Just a debug visual representation of the Linecast, can only see this in scene view! Doesn't actually do anything!
		Debug.DrawLine(transform.position, jumpCheck.position, Color.magenta);
		Debug.DrawLine(transform.position, interactCheck.position, Color.magenta);

		//we assign the bool 'ground' with a linecast, that returns true or false when the end of line 'jumpCheck' touches the ground
		grounded = Physics2D.Linecast(transform.position, jumpCheck.position, 1 << LayerMask.NameToLayer("background")); 
	}

	void PlayerController()
	{
		anim.SetFloat("speed", Mathf.Abs(Input.GetAxis ("Horizontal"))); //setting the float parameter called "speed" depending on the input from the horizontal axis

		if(Input.GetAxisRaw("Horizontal") > 0) // if d or right key is pressed
		{
			transform.Translate(Vector3.right * speed * Time.deltaTime); //move right 4 pixels at a fixed framerate
			transform.eulerAngles = new Vector2 (0,0);
		}
		if(Input.GetAxisRaw("Horizontal") < 0) //if a or left key is pressed
		{
			transform.Translate(Vector3.right * speed * Time.deltaTime);
			transform.eulerAngles= new Vector2(0,180); //rotates gameobject by 180 degrees horizontally
		}
		if (Input.GetKeyDown (KeyCode.W) && grounded == true) // If the jump button is pressed and the player is grounded then the player jumps
		{
			rigidbody2D.AddForce(Vector2.up * 200f);
			jumpTime = jumpDelay;
			anim.SetTrigger ("Jump");
			jumped = true;
		}
		jumpTime -= Time.deltaTime; //counts down in seconds
		if (jumpTime <= 0 && grounded && jumped)
		{
			anim.SetTrigger ("Land");
			jumped = false;
		}
	}
}

Thanks in advance

You could check the the velocity of your rigidbody2d.

if (rigidbody2D.velocity.y < -0.1)
{
   isFalling = true;
}
else
{
   isFalling = false;
}

This will cover not only jumping and then falling but falling off of a platform as well.
If you just want to check if it is falling after a jump then use this.

if (rigidbody2D.velocity.y < -0.1 && jumped)
 {
    isFalling = true;
 }
 else
 {
    isFalling = false;
 }