I feel a hard line running from a little under my breasts to my navel, is that my muscle repair? Is that normal?

Your description does sound like the muscle repair in the midline with firm scar tissue currently. This usually will soften somewhat over time. Fortunately it is not painful and has not affected you outcome.

I agree with others that this does represent the muscle repair site and that it will most likely improve. However, how much it will improve may be related to the type of suture that was used to perform the muscle tightening. The reason for mentioning this is that I have noticed more softening of this area if dissolvable suture was used as opposed to permanent suture. Not a lot of difference, but just a little. The other thing that affects how easy it is to feel the line is how thin you are... so the thinner you are the more you will feel this line.This concludes my hard line on your hard line. Sorry, I couldn't resist.

That does sound like your muscle repair though it is unusual for this to be able to be felt.  However, if you have a very thin upper abdominal flap, either from being thin to begin with or from liposuction) then this could be present.  At 7 months, I don't know that this will go away.  At least there is no associated pain.Have a good weekend and take care.