Chakras have nothing whatsoever to do with trance so I don’t know who told you that, but they’re wrong.
Most of the time you won’t feel anything, especially as a beginner. Just assume the spirit is listening.
It could mean anything from a build up of energy at that point, to the fact you were staring too hard at the seal and gave yourself a headache. It’s virtually impossible to say which it is.
You enter a trance multiple times a day, it’s a natural thing. You hit theta while taking a relaxing shower, it’s the level of trance where “ideas and inventions start coming to you” research different trance states and you’ll notice how you hit each nearly everyday. You’re probably frustrating yourself when you actively try.