hope all is ok, and we had the outbreak here too and I was reassured that one dose is still going to help. Also it's very rare to actually get whooping cough, and they only show the sick ones on tv... most are ok.
Also bronchiolitis is similar and my DS had it when 4 months and it scared me so much I went to hospital. That's my next point, if you are concerned at night, go to the hospital. They can and will help you there, especially in a young bub.
Thinking of you, it's not fun.
Also not sure where you are but there is a helpline in Syd (westmead nurses) and if you call and they listen to bub they will tell you what to do. I called them every night at midnight for about a week. xo
just saw you're in Melb, Im sure they'll have the same helpline. give the kids hosp a call and have it on hand xo