Simple POP UP Damage Script-Animation

Hi guys i am facing a perfomance problem and i dont know the reason is someone can see the code and answer me it will be helpful , I am trying to make a simple script that pop up the damage that you get like the photo below , the problem is that is working fine but i think is getting a bit laggy over time, i am creating i 3d text object that shows the damage and then i destroy it , because you can get multiple hits (creating multiple 3dtext object and then destroy it ) .

  public void PopUpDamage(float amount)
     {
         float currentTimeMillisecond = Time.time * 1000;
         Vector3 positionPrefab3DText = m_3DTextPrefab.transform.position;
         GameObject gameObject3DText =null;
 
         if ((currentTimeMillisecond - m_PreviousTimerMilisecond) > 1500 || m_EscalateTimes > 5) // If escalates 5 Times or time passed :: 1500 millisecond reset :: Starts From The Bottom ::
         {
             //Reset
             gameObject3DText = Instantiate(m_3DTextPrefab, positionPrefab3DText, m_3DTextPrefab.transform.rotation) as GameObject;
 
             m_PreviousTimerMilisecond = currentTimeMillisecond;
             m_EscalateY3DText = positionPrefab3DText.y;
             m_EscalateTimes = 0;
         }
         else {
 
             m_EscalateY3DText += 0.5f; //escalate Y = 0.5 Every Loop
 
             positionPrefab3DText = new Vector3(positionPrefab3DText.x, m_EscalateY3DText, positionPrefab3DText.z);
             m_PreviousTimerMilisecond = currentTimeMillisecond;
 
             //Anime The Damage
             gameObject3DText = Instantiate(m_3DTextPrefab, positionPrefab3DText, m_3DTextPrefab.transform.rotation) as GameObject;
 
             m_EscalateTimes += 1;
         }
 
         TextMesh m_3DTextMesh = gameObject3DText.GetComponent<TextMesh>();
         m_3DTextMesh.text = "-" + amount + " HP";
         Destroy(gameObject3DText, 0.5f); // Destroy 3d Text in 0.5
 
     }