Hello!
First of all, congratulations on taking such an adventurous step forwards! You have lots of energy in your playing. I've made some notes that hopefully help. But first of all, I would say, seek advice of a teacher. Apart from in very seldom cases being self taught has many limitations. Also, working with a more experienced pianist is always enriching, not just pianisticly, but musically!
Here are my notes:
In general, you need a stronger pulse. You need to feel the heart beat of the piece ticking in you

and express with the colours, not with changing rhythm or pulse, or both.
b1 listen after the chord for the voicing, your crotchets every time this motive appears are too long, you are counting 3 instead of 2. Is probably a mistake in the right direction, since is an important chord, but you desestabilize the structure. also, in the resolution you played b flat instead of natural.
b5 the forth beat, the rhythm is again unsteady, and careful not to overpedal in the beginning of next bar
b9 I would make more difference in the articulation, let the portato notes breath more and then respect all the rests, whilst still having the sound in your head.
b10 g-eflat interval, more legato, sing! you've really studied the scale, eh

?
The Allegro is great, I can hear you love it, but there are many more piano markings! All the first page only p with the rf and sf, more subito, going back to p!
Left hand could be a bit quieter and more steady.
b27 left hand rhythm! same 31. No rush. Hear each chord.
b49 50 I would not rit, it weakens it
The next section, you have work a lot on it,well done! there is more time in the leaps, no need to rush, specially b 75 and 79, and as much as you can, work towards the three layers, your base line (double bass e.g) the thirds (celli and violas?) and the upper part maybe flutes and basson.. ? Or violins and celli? But more voicing!
b88 Again, I think the rit spoils the effect, and in the next section feel more like hugging the keys, feel the difference in texture
b113 Don't rush! You know the passage very well, but it has to be part of the piece. More lyric
b134 thrid beat, left hand b flat
b136 hear your 4th and 5th finger, top line singing a bit more, and feel the syncopation of the left hand
b139 Rhythm!
b175 pp!!! More mysterious, listen to the intervals of the right hand, somehow it doesn't feel as if it's comfortable in your hand, and then b179 it seemed to struggle more than in similar passage previously.
I think you've made a great start in the piece. Sorry for all my pedantic notes, but since you said you had no teacher, I thought I'd give you something to think on! You might not agree with what I say though!!!! No problem

My only concern, is that in exams I have been too, cutting a piece short has never been an option! Have you checked that stopping there is something that is allowed for the purposes of your exam? It is a very frequently performed piece too, maybe it'd be nice to surprise the panel a bit more with something else? I wish you very good luck, and go to see a piano teacher/s!
Maite