22 weeks extreme pain

Grace
Hi Everyone,
So I just wanted to share an experience and see if anybody might know what is happening.
So about 3 days ago I felt a bit dodgey with a small amount of cramping went to bed early, when I went for a wee in the night and had a biggish chunk of snotty discharge on the tissue, didn't really think too much of it but of course googled it and mucus plug came to mind but knew at 22 weeks it wasn't that so put it all to the back of my mind and went back to sleep.
Last night I went to bed after being at a wedding all day and was shattered. Woke up about 3am by the most intense pain in my lower stomach and it kept me up for hours, pacing and trying to get comfortable. My husband who was dead to the world drunk and snoring his head off wouldn't have been much help at all so I just left him too it and eventually I went back to sleep. 
Baby is kicking lots as normal but I've felt uncomfortable most of the day today.
Starting to panic a bit, could this be a sign that things aren't right and something might be about to happen far too soon? Or is this normal pregnancy stuff? I didn't experience anything like this with my first which is why I'm a little bit nervous.
Any advise or comments would be greatly appreciated <3 xxxx