Over the years, I've discovered that there are a number of reasons why pain comes back after it has gone away supernaturally. I've recognized the reasons because I've ministered to many people whose pain did come back. When I minister to someone who just received healing, I will often inform them of what can happen after we part ways. If the person is not grounded in God's word, the devil immediately begins to work on their mind to bring doubt. Satan will do this in a variety of ways, including, engaging them in conversation with an unbeliever who doubts many things. Since we're all effected by the things we see and hear, it's important to shroud ourselves from unbelief and remain in the presence of the Lord.
But he must ask in faith without any doubting, for the one who doubts is like the surf of the sea, driven and tossed by the wind. For that man ought not to expect that he will receive anything from the Lord, being a double-minded man, unstable in all his ways. - James 1:6-7