I have had the exact same injury 3 times in the last 3 years. First time through was super frustrating and had numerous false starts..took about 7 weeks to get it right. Talked to many people about this and have come up with what works for me in terms of a recovery schedule. Unfortunately I have found it takes me about a month to conservatively get back to a decent place. Not what you want to hear but I think 2 weeks is probably not enough time to recover from this injury. My most recent episode was an initial injury in early May of this year...with Eagleman scheduled for June 8....felt the "pop" in the calf..those of you who have dealt with this know what I mean. Took 4 days off from running and tried again (a mistake in hindsight)...got 800m and pain again so shut it down.

Here is my recovery schedule that worked for me to get me to the start line at Eagleman
:
12-14 days of ZERO running NO STRETCHING...got some ART and/or work the foam roller after maybe 5 days...swim and bike a lot..do some aqua jogging. Then EASE back in...can't stress this enough.

REHAB - If there is any pain whatsoever you need to shut down immediately and take AT LEAST an extra rest day before attempting again. I have found that a very easy build of short jogs with walk breaks and rest days allows the strengthening and recovery to get back in the saddle. I cant stress enough that the jogs need to be SUPER easy and shut down at the slightest hint of pain. If you do get pain; stop... take an extra rest day, and consider a shorter effort with more walking.

AFTER 12-14 days of ZERO running:
May 17 - Day 1 rehab run :8x400 easy jog with 200 walk between each
Day 2 no running
Day 3 6x(4min jog/2min walk)...roughly 800/200
Day 4 no running
Day 5 5x (1200 jog/200 walk) + 1600 easy jog at end
Day 6 no running
Day 7 6x(1mile easy/1 min walk)
Day 8 no running
Day 9 5x(1.5mile easy/30sec walk)
Day 10 no running
Day 11 a bit sore..took extra day..no running...
Day 12 2x(2miles easy/30sec walk) + 4 miles very easy straight
Day 13 no running
Day 14 7 miles easy, then 2 miles moderate pace
Day 15 no running
Day 16 10 miles straight building to close to threshold in last mile
Days 17-22...taper week... Easy runs not longer than 5 miles
June 8 Day 23 Eagleman

So start to finish it took about 5 weeks....without my mistake of trying to come back too soon or shortening the taper (although the taper certainly helped recovery) I could have possibly compressed this to 4. If I had a race that I NEEDED to do and went in completely untapered is it imaginable to come back in 3 weeks but would have been a stretch and IMO would have risked a re-injury that could have knocked me out of my "A" race for the year (IMLP) in late July.

Since you asked...If I were you I would either skip the race or do aquavelo if offered. Not what you wanted to hear I am guessing.

Oh....BTW ...go see a doctor...he or she probably will have an opinion that may be worth more than most of the folks here on ST...esp me. ;-)