You should not see speech therapy just as a waste of time and money, it might work and even do wonders, and if I also suggest to self-evaluate the components of your stuttering, to judge if it is largely mental or largely neurologically, because the former means cognitive therapy will have more positive effects on you than speech techniques while the latter means the opposite and this evaluation will also be included in therapy and if your therapist is good enough he/she will accurately evaluate the components.(also don't forget therapy needs both your committments and the skills of therapist, and you also needs to give as many details as possible to your therapist) And if your stuttering is largely mental, I suggest to check my last post on this sub and hope that can help you a lot!