PMing through and through

I feel like startups have unreasonable and unnecessary self induced pressure at times. I am working as an APM at a gate management startup and all I feel is pressurized even though the release gets delayed whether due to faulty implementation or dev or qa or requirement change from business side which the PM has no control over. While all this is happening you are left to wonder where did you lack? Was it at Product Management or at Project Management because clearly both are not happening properly.

It's weird how so little at times is in your control and yet how all the blame you have to take because primarily it was your job to think it all through.