That's great that you are using this opportunity of lock down period in learning yoga, especially pranayama.
To let me clearly suggest, you may describe as to how you practice anulom vilom pranayama. It is therefore would not be appropriate to comment on this. But I can give a clue on this. If the vibrations/ tingling sensations do not appear comfortable and cause restlessness, then you should not continue. In that case, I assume that you are forcing breathing exercises by rigorous breathing. Therefore, you will need to calm down while doing pranayama practice in a very peaceful way and not to hold the breath. Also, you should reduce the time period of 15 minutes to 5-7 minutes only.
Such things happen when we practice meditation and this is because of pranic energy channels start working that were blocked earlier and this is a good sign. This too happens when we advance in meditation. In my opinion, Anulom vilon pranayama balances the Tri dosas in the body --Vaat, Pitta and Kaffa,they remove the impurities .It release the anxiety ,asthma and respiratory distress.Doing more than 15 minutes as you shall not healthy.Tingling helps to open the blocked energy channels but doing longer time can be harmful.To avoid the heavy feelings from the forehead, better to practice slowly please.
Still as a beginner, you are requested to kindly send me the steps you are using in practising the pranayama, so that I can analyse and discuss further.
In addition, you can also join us at free online yoga class being conducted during this lock down period.