BMW Repair Questions? Ask a Mechanic for Answers ASAP
Hopefully this is just do to low battery voltage. The first step will be to use a jump pack or jumper cables. If you use jumper cables let the other vehicle idle while attached for about 10-20 minutes to get a good surface charge and then try to start again.
The load noise is most likely the starter trying to engage and the lights flashing is common when the battery is low.
Once started, it takes quite some time to charge the battery while running. If you have a long drive it would be good to help bring the voltage up. Or if you have a charger, charge the battery and then visit you local part store and have them test the battery to make sure this is not a failing battery.
Let me know if I can help further. Please accept and I wish you the best with your repair.