Can you stall with not getting enough calories and protein??

I joind the site WWW.fitday.com So i could log all my food so i could find how just how much i am getting in, well after logging my foods for breakfast and lunch, protein did not add up to much and the calories for the two meals was only 455 calories. Thats probably why i have not lost much weight, i don't think i am eating enough. can anybody tell me, if that plays a big part in stalling, if your not eating enough calories?? I will continue to work on the calories and the protein and just see if it makes a difference, i will blog my results.