Move Camera around an object

Hello ! I am facing a problem regarding to move camera around an object with which I did perfectly... But my camera stops its rotation after rotating the given amount And I want my camera to rotate a bit after its rotation in order to give it a good look... But I m unable to do it... Your help would be appreciated. Thanks

     public Transform target;
 public float distance = 5.0f;
 public float xSpeed = 60.0f;
 public float ySpeed = 60.0f;
 public float yMinLimit = 10f;
 public float yMaxLimit = 60f;
 public float distanceMin = 5f;
 public float distanceMax = 10f;
 float x = 0.0f;
 float y = 0.0f;

 void Start()
 {

             Vector3 angles = transform.eulerAngles;
             x = angles.y;
             y = angles.x;
             // Make the rigid body not change rotation
             if (rigidbody) {
         rigidbody.constraints = RigidbodyConstraints.FreezeRotationX;
         rigidbody.constraints = RigidbodyConstraints.FreezeRotationZ;

             }
     }
 void Update()
 {



     if (target && Input.touchCount == 1 && Input.GetTouch(0).position.x > Screen.width / 2 && Input.GetTouch(0).phase == TouchPhase.Moved) //Just orbit touch without movement
     {
         Debug.Log("Orbiting! 1 touch");
         Orbit(Input.GetTouch(0));
     }
     else if (Input.touchCount == 2)
     {
         if (Input.GetTouch(0).position.x > Screen.width / 2 && Input.GetTouch(0).phase == TouchPhase.Moved)
             Orbit(Input.GetTouch(0)); //Movement was touched second
 
         else if (Input.GetTouch(1).position.x > Screen.width / 2 && Input.GetTouch(1).phase == TouchPhase.Moved)
             Orbit(Input.GetTouch(1)); //Movement was touched first
     }

 }

 void Orbit(Touch touch)
 {
     x += touch.deltaPosition.x * xSpeed * 0.1f /* * distance*/;
     y -= touch.deltaPosition.y * ySpeed * 0.1f /* * distance*/;
     y = ClampAngle(y, yMinLimit, yMaxLimit);
     Quaternion rotation = Quaternion.Euler(y, x, 0);
     //distance = Mathf.Clamp(distance - Input.GetAxis("Mouse ScrollWheel") * 5, distanceMin, distanceMax);
     RaycastHit hit;
     if (Physics.Linecast(target.position, transform.position, out hit))
     {
             //distance -= hit.distance;
     }
     Vector3 negDistance = new Vector3(0.0f, 0.0f, -distance);
     Vector3 position = rotation * negDistance + target.position;

     transform.rotation = rotation;
     transform.position = position;

     

 }
 public static float ClampAngle(float angle, float min, float max)
 {
     if (angle < -360F)
         angle += 360F;

     if (angle > 360F)
         angle -= 360F;
 
     return Mathf.Clamp(angle, min, max);
 }