My car is taking about 5 seconds to start wat could be causing this problem

The fuel pump could be weak. It may take several revolutions of the engine to build up enough fuel pressure to start the car, when normally there is enough fuel pressure there to start the car within a second or two of cranking it over. The fuel pump could be the problem

Hard starting could be caused by leaky valves.
If the petrol consumption has increased and it doesn't go up hills too well, then take it to a garage and ask them to check the compression.

If it is low then the valves are likely to be worn and they need to be ground in to improve the seal.

There could be multiple problems. Depending on where you live cars that are in colder conditions tend to have more problems starting up and the take a while. If you are are in a warmer climate I would say that if you haven't changed your starter or alt that they might be becoming weak from time and they should be checked by a mechanic.

If there is no other problems that are connected to this then I would just keep watching until another problem comes up. Some times one problem isn't enough to narrow down the solution.