private void checkUpgrades() {
        if (jumpMultiplier != 1.0f || speedMultiplier != 1.0f || invulnerable != false) {
            long currTime = System.currentTimeMillis();
            if (currTime - jumpUpgStart >= JUMP_DURATION) {
                jumpMultiplier = 1.0f;
                jumpUpgStart = 0;
                activeBuffs[0] = -1;
            }
            if (currTime - speedUpgStart >= SPEED_DURATION) {
                speedMultiplier = 1.0f;
                speedUpgStart = 0;
                activeBuffs[1] = -1;
            }
            if (currTime - invulUpgStart >= INVUL_DURATION) {
                invulnerable = false;
                invulUpgStart = 0;
                activeBuffs[2] = -1;
            }

            // Oppdaterer aktive buffs ints (for tegning)
            if (activeBuffs[0] != -1)
                activeBuffs[0] = Math.round((currTime - jumpUpgStart) / 1000);
            if (activeBuffs[1] != -1)
                activeBuffs[1] = Math.round((currTime - speedUpgStart) / 1000);
            if (activeBuffs[2] != -1)
                activeBuffs[2] = Math.round((currTime - invulUpgStart) / 1000);

        }
    }