Brake petal goes to the floor then you can pump it up.

If the system was fine before you changed the discs then it is most likely that the system has air in it or you have a leak at one of the cylinders. Double check your work, inspect the cylinders for leaks. on the rears you can pull the handbrake on and off a few times to adjust the rear pad position.

Bleeding is done one wheel at a time. Start with the wheel furthest from the master cylinder and work your way closer ( RRear, LRear, RFront, then LFront). The order is not really that important since they are on separate circuits on modern cars with ABS systems. But there is no reason not to stick to the tried and tested method. Keep the fluid topped up and if possible use a clear pipe on the nipple of the cylinder you are bleeding so that you can see if there are air bubbles in the system.

the bolts are getting really hot because the friction of the pads running on the rotor the whole time whilst driving.
the pedal problem could be a few things but the most likely is either that the brake fluid needs replacing because it's got water in it,
there's air in the lines or the brakes master cylinder seals need replacing due to age.

Check the pads/rotors to see if they need to be replaced.
Check the brake fluid level. If low it could mean the pads/rotors need to be replaced. If replacing also replace the brake fluid.
Two years probably means you need a brake job.

Otherwise you may have air in the brake lines which you can bleed off.

if you cant find any leaks in lines or cylinders or calipers u probaly have a bad booster
see lots come threw my shop like that but also their is a vacum line that runs to the booster and it hooks to a plastic valve that goes in to the booster those get gloged and you loose pedal as well try replacing that before you bye a new boooster

Something doesn't sound right, you shouldn't have to remove the brake line to install pads. Did you have to do this on both sides? Do the new pads and the old pads look the same? Did you get the caliper on crooked? Just recheck your work first before replacing more parts. When you install the caliper, You have to hook the pad on one side first before you slide it over the rotor.

Hello;
The parking brake cables may be stretched and in need of adjustment. Follow the cables along to a nut. Then you can tighten the adjusters up on both sides until you have the proper tension. Also make certain none of the brackets are bent or broken that the cables ride through.
Thanks;
RPM Northwest

You have air in your break lines. The two ways you can solve this problem is have the breaks blead to get the air out of the lines, or you can take the top of the break reservoir and pump your breaks to the floor. DONOT DO THIS With the car moving. What this will do is force the air to the reservoir.

You need to replace the master cylinder. If all else is good and the petal goes to the floor, that's really about all it could be.

are your rear drums set up? why did you bleed the brakes. when only when you installed new pads?