Thank you for sharing your dream/vision with us. Please take everything that I share to the Holy Spirit as He Alone gives the accurate interpretation.
It sounds like this might have been a vision/or actual encounter. The dark tunnel represented the “dark” time that you were going through and a play of words that there is light at the end of the tunnel. Our Lord Jesus will do whatever He wants to do to reach His children and even those who do not believe in Him and/or disobedient. That is how much He loves every human being. Our genuine tears touch him and moves Him to act; read John 11 as an example of many. He wanted to comfort and encourage you and chose to use the method that you described. Hallelujah! I’m glad that your cat is doing better.