Gurudev, I have been a follower of the Radhaswami tradition for a very long time. In my desire to meet you, I attended the Happiness program and learnt the Sudarshan Kriya. Now I feel guilty that I am not doing something wrong. Can I follow two different spiritual traditions together?
There is no need to feel guilty at all. See, you started following a particular spiritual tradition sincerely and did a lot of good service there, as a result of that you got the gift of coming to this tradition. But once you are practicing the meditation practices of this tradition (of The Art of Living), I would suggest you to not mix up them up with what you were doing earlier.
Do not try to change or mix the techniques taught here with some other ones you have learnt before. Follow the techniques and the approaches taught here as you have learnt it. You are also receiving the knowledge from that spiritual tradition, so continue to do so and honour it.
All knowledge is one – the knowledge of the Self. It is just expressed in different ways by different people and spiritual traditions.
If you really look at it, there is no conflict between any spiritual traditions. It is just a trap of the mind, so you need not worry about this and take it too much to heart. Honour everyone and every tradition, but follow one spiritual tradition with all sincerity.