There was a thread on here a little while ago about just how much we (i.e. everyone on Mumsnet who was trying to sell a house at the time) hated estate agents 
But there was a really useful post from someone who I think might have been one of the genuinely nice estate agents ... she said that, if you are getting NO viewings, your house is at least 10% overpriced. If you are getting lots of viewings but no offers, it is at least 5% overpriced (I think).
We were trying to sell a house at the time, and had had loads of viewings but no offers. We immediately dropped the price; had 4 more viewings and an offer (which we accepted) within 2 weeks.
I know it's hard when you need a certain price in order to buy something else, but could this be the case here? Have you asked estate agents what other houses are selling for in your area? I'd always assumed that most buyers would be like DH and me, in that we look at houses that are at least 10% over our budget and then make cheeky offers if we feel the house is overpriced comapared to others that we've seen. (We bought our current house for 12% less than the original asking price, 2 years ago).
In our area (south coast), houses are definitely moving slowly and taking at least 12 weeks to get offers, whereas a few years ago you could get a full asking-price offer within a week of going on the market. Buyers have to have much higher deposits these days, and there aren't so many mortgage products around, and we're all waiting on tenterhooks for the BofE to raise the base rate .... hence, the housing market is a bit stagnant.
So - yes, I think that what you're experiencing is normal for the current economic climate.
Hope you get some viewings soon.