Pennsylvania and Indiana are both members of the Driver's License Compact (DLC). The DLC requires member states to report tickets received and convicted of out of state back to the state in which the driver is licensed in. It is then up to the home state's laws to determine if the violation will be placed on the person's driving record and assigned points.
The Indiana Bureau of Motor Vehicles (BMV) states that for moving violation convictions, which IN has a corresponding violation, the offense will be placed on your driving record along with the allotted points. So if you pay the PA speeding ticket and thus are convicted of it then the Pennsylvania courts should inform the IN BMV and the offense and points would be placed on your motor vehicle record (MVR).
You can contact the Pennsylvania court before the due date of the ticket to see if there is a way to reduce this speeding citation to a non-moving violation or take traffic school in order to get the ticket dismissed. If either of these are options that you can take than check with the court but typically the speeding offense would than not be a conviction that they would notify your home licensing agency about if you were able to do one or the other.
If you end up paying the speeding ticket as it was given to you than it appears that PA would inform Indiana and thus it would go on your MVR and be assigned points. This also means your insurance company would see it the next time they pull your driving record and thus it could affect your insurance rates.
Since this is your first ticket than it may only mean you lose a safe driver discount however it is up to your insurance provider's rating system. Your insurance agent should be able to tell you about your insurance company's rating system and how getting one traffic ticket could affect your premiums.