Do I need to check out and check in my baggage again in transit airport?

Your title and your question don't match. So I'm not sure what you're asking, but I'll answer both questions.

1. Do I need to check out and check in my baggage again in transit airport?

   Yes. You must gather your checked bag and pass through US customs at the airport where you enter the country. Then you must re-check your bag (even if on the same airline), and pass through TSA security before boarding your onward flight.

2. Do I have enough time to check out and check in my baggage?

   Maybe. 1.5 hours might be plenty of time, if you can get through US immigration and customs and TSA security quickly. If there are no lines, you could be through all of that in 10 minutes. On the other hand, if it's a busy time of day, it could take 2 hours just to do that. It's really hard to predict sometimes. If you can tell us what time your flight arrives, someone familiar with the Philadelphia airport may be able to provide additional insight as to the expected delay at that time.

Adding to Flimzys answer: In normal conditions you should have enough time to make the connection in PHL but you come in at a time where a lot of the European flights get in as well, so it will be busy and there is a non-zero chance that you'll miss it.

If it's all booked on the same ticket, the airline is responsible of getting you to BMH. If this will require to stay the night, they will have to put you up in a hotel and give you some food vouchers are well.

If it's not booked on the same ticket, you carry all the risk and have to negotiate with the second carrier how to get to BMH. This will include almost certainly a hefty change fee. Consider a travel insurance that covers this type of thing.