Last time I had "real" contractions that were actually prodromal labor for about 16 hours straight until my water broke, at which time I went into active labor. Active labor lasted another 20 hours. The way I know it was prodromal labor is that the contractions came consistently 7 minutes apart - never less. They were definitely "real" in the sense that I was in early labor, but I know now that based on the timing, I was not in active labor, and hence, I should have just gone about my day and tried to function as normally as possible. I made my labor WAY more difficult than it had to be by not just going back to sleep.
As far as what they felt like, they were unmistakable and unlike anything I had ever felt before. I had to get on my hands and knees and sort of rock through them. If there is a question in your mind, it's probably braxton hicks - when you are going into real labor (even early labor) it's really unmistakable.
This time around, I won't treat any contractions - no matter what they feel like - as real until they are less than 4 minutes apart. Before that, they aren't doing anything and I need to prepare myself for real labor by sleeping and eating normally. I would recommend that to all first time moms. No matter what your contractions feel like, unless they come consistently less than 4 minute apart, they may or may not be REAL, but it doesn't matter because you are not yet in active labor, so you should do your very best to keep living your normal life so that when you do finally go into active labor you are fully prepared, and not exhausted and depleted.
Not sure if that's helpful for you!