Harman, bf is such an emotional subject that it is only natural to feel upset if things didn't go to plan.
I am in a similar situation to yourself, have four kids (hence name!)and am completing Mother Supporter training with the ABM, with the view to go on for full BF counsellor training.
However, I didn't manage to BF DC1 and for various reasons only managed a few days then onto FF. He is the only one of the four to have asthma and was hospitalised on a few occassions as a toddler.
I feel horrendously guilty about it, and can't help but think that maybe it would have been different if I'd BF. However, we can't undo the past and maybe he would have gone on to develop asthma even if he had BF.
I think the fact that you have had difficulties with bf will make you stronger and a better supporter becasue of it?