My ear is really really blocked? How do I unblock it?

Last night I was on my laptop and all of a sudden my left ear became blocked. I thought it would pop by itself within a few minutes but it hasn't gone yet. I went to sleep with it, and I woke up in the middle of the night hearing a bit of a crackle and it was unblocked, but when I woke up this morning my ear was blocked again. I've tried yawning, sneezing, holding my nose and blowing and it just doesn't work. I can hear myself speak more than when it's unblocked, I can hear my mouth much better... but it's so bloody ANNOYING! I might book an appointment with my GP later, if it hasn't gone within a few hours. Is it an ear infection? I've had a throat infection on/off within the past 3 weeks...