Luckily these days at least I have not had a pretentious beginner student suggesting to me that he or she wants to do more pranayama! Earlier, when I was a callow teacher, and vulnerable (that makes these audacious types more audacious:) I have had such requests: a student coming to say that he or she is bored with a particular pranayama and wants to do something different or more. Now I know better. Unless you show evidence that you are, on your own, practising what I have thought you, you are not qualified to more growth in pranayama. That is somewhat like meditation, and needs a lot of maturity to invite daily practice and deep dedication. Where that is lacking, u are just flirting with something that deserves something more than that vapid attention!
Also, for intense pranayama, your diet has to be modified: no salt or spice. No stimulants. No media or onslaught of information that can distract or agitate the mind. You need to have less work such as you may be doing now -- commuting etc (this is also true for intense meditation, btw). That is why it has to be done in a protected space like a retreat, ashram, and under expert supervision. Otherwise, you will break out as the toxins release -- skin eruptions, ulcers, fever, blood pressure fluctuations. And the less said of the mind, and the effect on it, if intense pranayama is done unguided, the better!!