I’m going to put myself out there now and say that waiting for a reply to a romantic text is one of the most excruciating things to have to endure.
So why do we feel so bad, waiting? Well, get this: I read, in a neuroscience book by Susan Greenfield (I wasn't seeking this out, you understand, it was a happy aside to something else I was researching) that there is a scientific reason that can be attributed to the post-text lull. When we send a text or email (or whatever) we experience an adrenalin surge in anticipation of what might come to pass. The downside, like with any upper, is that as it becomes increasingly apparent that a response isn’t coming our dopamine levels plummet. Literally, our mood juices drop. It's scientific fact! I don't know if that makes me feel better or worse, but, you know, FYI. Bear it in mind next time you’re hovering on the send button.