Feeling pain and swelling in finger tips?

This has been happened many times with me. During sleep somethings i wake up with panic and fear, my heartbeat after getting up is really fast and i feel fear. With these all, i feel swelling and pain in my finger tips and shivering in the body. I feel like a lot of blood suddenly flowed into my arms which causes this swelling feel and pain..

I am high BP patient and Dr has recommended my one tablet a day with an another relaxation medicines.

My age is 25 and i am skinny or may be fine for my figure but not over weight..