Hi DaftChris, and welcome to DW Mahayana!
As to doubts, remember they are normal, and they are also a very good, healthy sign. It is natural and normal and intelligent to doubt...the only difference here is you also have your own practice, realisations, and undeniable experience/breakthroughs to balance those doubts.
So it is always doubt, faith, doubt, faith, doubt, faith, and so the practice flows.
Well wishes, and happy discussing!