I'd advise that you should cut down to one "speed" session per week.... in fact, go further and give it a kick start by having 4 weeks without ever getting out of breath.
Instead, replace fast sessions with slower, but longer runs. Concentrate on building up your long, slow run mileages over the next month.
You need to build a strong aerobic base in order for your speedwork sessions to be effective. My strong guess is that you've not got the balance right at the moment.
It takes 6 weeks to have a really big effect... so ideally, keep it long and slow until then and then have a go at your favourite tempo run, and see how you do. I'd predict that you'll be delighted.
Have a look at the Hadd thread..