12 days off running.... went for a bit of a tester. 3.8 miles. Intended pace between 10 to 10:30. Just downloaded my Garmin. First mile was 9:44... then averaged 9:01 for the remainder of the run. And I never even knew!
Anyway... the back felt fine. It's now just a matter of hoping it's still fine after a night's sleep!
Are they an identical model? Or has there been a styling update since your old ones?
If your old ones are well used, then the support does tend to go a bit, and new ones can feel stiffer... in which case they could perhaps just do with breaking in on some short easy runs. Do this now, rather than waiting for April!
But you say they're a tight fit. Obvious questions... are your feet a bit more swollen than normal? have you DEFINITELY been sent the right size?
My final 'pearl of wisdom' is that buying online will sometimes feel like it saves you money.... and sometimes it does. But sometimes it doesn't.
I'd always recommend buying from a shop, then you try on the actual shoes that you're going to own. Maybe (or maybe not) it might cost a few quid more, but if buying online goes wrong just once in six times (for shoes, that may be once in 3-5 years), then it can end up costing you all the money you think you saved on the other successful 5 occasions.
My guess is yes.... because the the 15kg weight is making you lean forward at an angle to which your legs are not well adapted.... Your toes are likely to be pointing further upwards than normal. Instead of relaxed ankles, your feet are more likely to be at less than 90degree angle... as in uphill running, so putting more stretching stress on the a achilles... And that's before you take account of the significant extra weight you're transmitting to the ground with every step.
I know what you mean about changing priorities. Cricket takes all day, and you can't help thinking that you could be using some of it to be out for a run! Having said that, if you're not a member of a sociable running club, then I'd be loathed to give up the camaraderie and team spirit involved in the cricket pavilion. I'm sure there's room for both.
Not sure if I'll do an autumn marathon this year - I'll decide after Brighton
Which marathon(s) have you got lined up this year? ( the way you're going, then the 3:50 should be the minimum target you go for!)