this.state = {
      btnTesting1: {
          loading: false,
          buttonText: "EXTRACT",
          isDisabled: false
        },
        btnTesting2: {
          loading: false,
          buttonText: "EXTRACT",
          isDisabled: false
        }
}

<Button
        id={`extract-${value.sectionID}${value.specimenID}${value.requestID}`}
        onClick={this.onChange}
        disabled={value.phlebo_sampleSpecimenID}
        >
        {value.phlebo_sampleSpecimenID ? 'EXTRACTED' : 'EXTRACT'}
    </Button>

onClickBtn = evt => {
      const buttonId = evt.target.id;
        this.setState({
          [buttonId]: {
            loading: true
          }
        });
       etTimeout(() => {
          this.setState({
            [buttonId]: {
              buttonText: "EXTRACTED",
              isDisabled: true,
              loading: false
            }
          });
        }, 2000);
        console.log(buttonId);
};


 <Button
          id="btnTesting1"
          onClick={this.onClickBtn}
          loading={this.state.btnTesting1.loading}
          disabled={this.state.btnTesting1.isDisabled}
          >
            {this.state.btnTesting1.buttonText}
 </Button>
 <Button
          id="btnTesting2"
          onClick={this.onClickBtn}
          loading={this.state.btnTesting2.loading}
          disabled={this.state.btnTesting2.isDisabled}
          >
            {this.state.btnTesting2.buttonText}
 </Button>