A couple of months ago, I had a subungual hematoma, which eventually caused the nail to fall off. After a while, a new nail began to grow (which looked oddly deformed (bottom was alright, but top looked "bloated", it formed a large "bump").

I thought it was normal, and that the nail would eventually grow out the top and I could trim off the deformity, but it seems a new nail has begun to grow OVER the old nail, and from what I've read, its usually supposed to grow under the old nail and push it out. The new nails grown about halfway up my toe, and the old nail is giving me problems (ingrown toenail) and I'm going to start soaking it in Epsom salt, but I have a couple of questions:

1) Is this a serious problem?
2) Are the different processes related? (Multiple toenails ingrown toenail)
3) If so, how can I treat it at home, or should I get professional help?

Thanks.