Should you be worried if your girlfriend doesnt text you back?

I get worried BAD when she dosent text back, its not that i think she dosent wanna talk. I just get worried if she alright or if shes in a situation where she cant answers back and theres nothing you could do about it. I guess i just love her too much, but just hope shes alright. Her phone prolly died or she left it in the ither room.