Orbs are at the following points:
Wave 1-1:
Plants
Health Orb
Butterfly
Butterfly
Butterfly x 2
Health Orb
Plants firing birds x 2
Plant shooting
Plant firing birds
Plant shooting
Health orb
Final butterfly
Final birds
Wave 1-2:
Worm x 1
Flying thing
Health orb
Worm x 1
Flying thing
1st tunnel
Red thing
Worm
Bomb Orb
2nd tunnel
Worms x2
flying things
Health Orb
Worm
Spinning things
Health Orb
Worms x 2
Flying things
Health Orb
Very quick flying things x 2
Wave 1-3:
Flying things
Bomb Orb
Flying shooting things
Health Orb
Flying things
Health Orb
If I've missed any or if you have any questions or complaints, post below.