AMP usage for heat cable, a/c, herpstat, etc.

Hey guys, anyone ever have an issue with not having enough outlets to plug all the necessary equipment in? i have 2 dual wall outlets in a room. I have a portable a/c that probably utilizes around 12 amps, a portable heater that is also around 12 amps, have 1-150 watt heat cable and 2-100 watt heat cables, and a herpstat 2. Right now the A/C is more important since its summer but i noticed when i had both the heater and air conditioner/fan plugged it, all equipment would eventually turn off from overload. I then switched the A/C to its own wall outlet and it on a 12 gauge extension cord for safety and its been good. However, on the other outlet, i would still have 3 heat cables (maybe 4), a heater, and the herpstat 2 on one surge protector in the wall outlet. Anyone have recommendations to accommodate this equipment?