It sounds like you’ve had a dread perm performed. I have seen timelines of these working out pretty well for people. We generally discourage them because there are less expensive and less damaging ways to get your hair to lock up.
I will link you some timelines showing images of others who say they started with dread perms (I apologize for the ugly links; tumblr’s coding has been acting up for me lately!):
http://members.home.nl/romkesijtsma/DreadlockTimelines/simone.htm (not a dreadperm start, but thin locks to start that thickened quite a lot)
http://members.home.nl/romkesijtsma/DreadlockTimelines/suzanne.htm (a thin dreadperm that thickened)
By the way, that website is not at all affiliated with dreadlockinfo, they just have some fabulous timelines!
Your locks should certainly thicken with time. I’d be highly surprised if they didn’t. Allow them to loop up and mature with minimal maintenance and you’ll be more likely to have thicker locks. On the other hand, if you do monthly crochet hooking and minimize your loops, this will likely cause your locks to mature a bit thinner as it prevents them from bunching up as they lock up.
You almost certainly won’t have to combine them. Unless you were given over 80 locks or something, on your hair texture, your hair is very likely to thicken as it matures and locks up.
As for the visible scalp, that issue usually goes away as your roots poof out and get a little frizzier (a normal part of having locks that we ALL face). Don’t worry about your sectioning for now. As long as you were given sections in a bricklay pattern rather than a grid pattern (i.e. they were staggered so one vertical part didn’t fall directly above the other), then it will be fine.
And, finally, just give your locks some time. In 3 months, they’ll look a lot different. In 6 months, they’ll be super cool and starting to mature.
If you wind up not liking them, it is 100% possible to brush them out or cut them off. It’s up to you. You can always redo them.
I advise you not to worry so much and to just give your hair some time.
I hope this was helpful.