Loss of horny feelings

This is my thing i get super exited when my girlfriend sends me some special pictures right.
she dosent live with me yet since we just started college but my thing is everytime i finish masturbateing i lose all my horny feelings and such almost instantly like i want her so bad and stuff and im looking at the pics and then i cum and after that. i dont want to look at anymore pics or porn or masturbate or anything like that. total loss of wanting anything sexual. is this normal or something?