wa iyyak,
bro you may find discussion about this matter in the Books, maktubaat and mawaiz of ahlul tareeqat. Such as maktub(letter) no107 in 3rd volume of Maktubaat By Imam Rabbani Hazrat Mujadid Alfe sani sirhindi R.A ,Also the technical understanding of lataif are well explained in Hujatullahil baaligha by Shah wali ullah R.A. How Aql, Qalb and Nafse come into play. Also maktubaat of khwaja masoom R.A discuss about Qabz. And many other books.....But nothing substitutes the company and education from a true mentor/shaykh.
They say Qabz can happen either by having commited some sin which causes it, or sometimes its from Allah. In the first case astaghfar and sincere taubah helps, in second one must continue his shaghl/nafl ibada wihtout paying attention to whether one is enjoying his ibada or not, often the test is to check whether the slave is doing ibada for his nafse or desires or is it for Allah, unconditionally. And if the person stays steadfast, imense barakah and rehma showers upon him. Neverthless, istaghfar and keeping the company of sincere Ahlul zikr is the best medicine in all cases.
And offcourse this is in no way any expert or exhaustive discussion on the matter.Test and trials, haals and ahwals come in all forms.