Hello,
I'd really appreciate some advice guys!

So get this, I was starting to tackle some good distances. I was hitting a 19miler with plenty of time to go to the London Race Day; this was late February, perhaps a little too early.
Then a lot of commitments forced me off training for a while, and I took two weeks off.

I then leapt into a Half Marathon race (bad move) which I completed in 1hr 51.
I allowed loads of rest, and then proceed with a casual 10miler later in the week.

The next week I got done over by an inflamed muscle in my lower back and this had me out of running for close to a month.

I finally recovered from this injury just a few days, but now I'm in the tapering "zone" so I'm only really running here and there - all seems good, however.

Am I still fit to run the Marathon? A part of me thinks I can, a part of thinks I can't. I'd push these thoughts off if I hadn't had any hiccups, but just coming out of an injury less than two weeks prior to the day has me concerned.

Would I be able to make the distance if I took it real easy (i.e. 4:30 time)?

Thanks guys,
Eason