I am about 4 months pregnant and I had terrible cramps and leaked a lot of fluid last night, but now I feel fine. What is going on with me?

I am about 20 weeks/4 months pregnant with my second child, and all day yesterday I was having the worst cramps that would come and go. Then some time after I went to bed last night, I woke up and my underwear were soaked and I had no idea why because I know for sure that I have never and would never leak that much... show more I am about 20 weeks/4 months pregnant with my second child, and all day yesterday I was having the worst cramps that would come and go. Then some time after I went to bed last night, I woke up and my underwear were soaked and I had no idea why because I know for sure that I have never and would never leak that much urine. I went to the bathroom and then tried to go back to sleep, but the cramps were so bad that I could not get to sleep. Then after awhile I started leaking a ton of fluid all at once. Unfortunately my husband has to work nights and weekends so he wasn't home, but I called him on his cell phone and told him what was going on. I couldn't find much info online, but I found out that it could very likely be amniotic sac membrane split, which means that 2 sealed membranes split a little bit and you leak fluid. This is not generally supposed to be something too serious, and I really did not feel like going to the hospital because our hospital is TERRIBLE and there is always a ridiculously long wait at the ER. I'm talking an hour before they will even take you to the back, if you are lucky. So I just told my husband that I would wait and see if anything else happened before having him come to take me to the hospital. I took one Tylenol and the cramps were still terrible after that, but I managed to get to sleep around 3:30 am which was about an hour after taking the Tylenol.
Update: I woke up at 7 am when I heard my 2 year old daughter crying, and I felt a lot better and hardly felt any cramping or leaking at all. Now it is 9:15 and I still feel pretty good. I have a checkup tomorrow, so I feel like I can easily address this issue and make sure the baby is OK at that time. But I was just... show more I woke up at 7 am when I heard my 2 year old daughter crying, and I felt a lot better and hardly felt any cramping or leaking at all. Now it is 9:15 and I still feel pretty good. I have a checkup tomorrow, so I feel like I can easily address this issue and make sure the baby is OK at that time. But I was just wondering what your thoughts are. What do you think is going on with me and why? Please try not to be too hard on me.
Update 2: Edit: it is 11 am now and I still feel fine.