i just saw your blog ..... worried about yourself .... no you don't have any problem!
you haven't ask your girl neither has she asked you for lovemaking. as i an see you both want it. but relax man! and take a deep breath... but take bold step now and ask her. but make-love. not baby yet ..... use a condom
things like this normally happens when having the girl for the first time, and this is due to anxiety... you tend to think of pleasing her and on the long run forget to allow her please you too, hence you start sweating , shivering, and consequently loss erection. the girl need to understand your plight and be patient you both need mutual communication with each other.
whenever you are with your girl and want to make love to her just relax your mind, just gently start with fore play.... petting, caressing, and kissing. never be in a rush, and talk less or you will spoil the tempo! there is nothing wrong with you gently caressing her boobs and even fingering her slit..... i bet you will be charged up to satisfy her eventually.