As others have said, don't be too concerned if your midwife is not concerned. As long as you are feeling well now, and bubs is moving and kicking you lots, then it is probably just a virus which is out of your system. Severe diarrhoea can sometimes trigger labour, and this is why some women induce with castor oil, but if you have not gone into labour by now then you will probably not have to worry about it until your EDD or beyond.

As always though, if you experience any more cramping or diarrhoea then ask your midwife to give you a check over just to be safe.