Physic2D.overlapCircle Instantiation

In my game, I am spawning spikes at a random point in an area on the y axis. The problem is that I don't know how to make the spikes not get instantiated on top of one another. I have looked into using Physics2D.overlapCircle, but idk how to implement it. If there are any other means for doing this, please tell me. Here is my spawning code:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class SpawnSpikes : MonoBehaviour 
 {
     Vector2 cameraPos;
     public GameObject twoSpikes;
     public GameObject twoSpikesLeft;
     private Vector2 screenSize;
     Vector2 spawnPositions;
     Vector2 spawnPositionLeft;
     Vector2 yValue;
     Vector2 xValue;
     Vector2 maxY;
 
     void Start()
     { 
         cameraPos = Camera.main.transform.position;
         xValue.x = cameraPos.x + screenSize.x;
         screenSize.x = Vector2.Distance(Camera.main.ScreenToWorldPoint(new Vector2(0, 0)), Camera.main.ScreenToWorldPoint(new Vector2(Screen.width, 0))) * 0.5f; 
         screenSize.y = Vector2.Distance(Camera.main.ScreenToWorldPoint(new Vector2(0, 0)), Camera.main.ScreenToWorldPoint(new Vector2(0, Screen.height))) * 0.5f;
         Debug.Log(spawnPositions);
         InvokeRepeating("spawnTwoSpike", 1.0f, 0.4f);
     }
 
     private void spawnTwoSpike () 
     {
         Instantiate(twoSpikes, spawnPositions, Quaternion.identity);
         Instantiate(twoSpikesLeft, spawnPositionLeft, Quaternion.identity);
     }
 
     private void FixedUpdate()
     {
         cameraPos = Camera.main.transform.position;
         yValue.y = cameraPos.y + screenSize.y;
         maxY.y = yValue.y + 10;
         spawnPositions = new Vector2(xValue.x + (screenSize.x * 2) * 0.5f, Random.Range(yValue.y + (screenSize.y * 2) * .5f, (yValue.y + (screenSize.y * 2) * .5f) + 10));
         spawnPositionLeft = new Vector2(xValue.x - (screenSize.x * 2) * 0.5f, Random.Range(yValue.y + (screenSize.y * 2) * .5f, (yValue.y + (screenSize.y * 2) * .5f) + 10));
         Debug.Log(spawnPositions); 
     }
 }