Pact double down

A warlock either renegotiates their pact or adds on to their already existing pact. With this their pact patron allows them to access lower level spell slots at a cost.

At Level 5, you gain two 1st level spell slot. At level 9, you gain two 2nd level spell slot. At level 13, you gain two 3rd level spell slot. At level 17, you gain 1 extra spell slot for each spell slot gained by this feat.

Whenever one of the spell slots are used from this feat, the user takes 1d4 psychic damage (Cannot be resisted/ignores immunity).