I don't think you were being unnecessarily harsh, Helen - you're perfectly justified to take umbrage to unfounded comments about your health and wellbeing.
This is such a stressful time for everyone here (which is why most people end up on these threads in the first place) that people need to think a little more carefully about how they reply to others. It's all well and good to give advice and to make suggestions - again, another reason why ladies are on here in the first place - but to heavy-handedly inform someone that there is clearly something wrong with them is not a positive, or appropriate, course of action.
The reason I've loved this thread from it's original incarnation is that everyone seemed really grounded and sensible when dealing with the realities of conception, and indeed the subsequent problems associated with ttc, and indeed pregnancy. We all have our hysterical moments, and even though it's pretty much impossible to imagine the difficult situations that some users of this website, and people we know in the 'real world', have been in throughout their periods of ttc, it's a saving grace that most women that I've come across on here have been generally rational and aware that there's a difference between giving gentle advice and stuffing opinions down throats - even when they've experienced tragedies I can't even bear to dwell on.
If I thought there was a problem with my body or my pregnancy I'd love to have people try and explain what the problem could be, and probably gently suggest ways of solving the issue or perhaps giving an account of their own experiences. To be honest, without you girls on here I think I would have gone stark raving mad from the beginning because it's difficult to go through any of this when you're trying so hard to keep it from those you are closest to. However, what I would never want was to be told that there was certainly something wrong with me/I hadn't acted in the correct way/that something I'd innocently done had ruined my chances of ever becoming pregnant (and unfortunately I have seen comments to this effect).
Give advice and tread gently - it's what we all want, and honestly, what we all need at times. Unhelpful comments should be left at the door.