Wax.
Go home, cold shower or bath. And use NOTHING on them for 48 hours - no creams, lotions, soaps, powders, ingrown solutions - nothing.
Just cold showers til the pores close again and the swelling (heat) goes down.

It is the only thing that has worked for me - I am a newly converted waxer - forever shaved and used creams and always the ingrown, red rashy looking stuff - always. The last 2 times been waxed, done the above and NO ingrowns. NO rash. NO itch. Nothing. Even in Perth sweaty heat.

HTH