If you see an opportunity you need to take it. You need to to grab it with both hands even if it means working out how to do it or pay for it later. You don't want to think "what if?" What if I had done that? What if I had taken that opportunity?
Days, weeks, months, years later you don't want to thinking that dreaded question, "what if."
Why don't you join me as we try to take every opportunity that is available to us?
However, don't do as I have done throughout my life, attack it half assed. Give it your all and if it doesn't work out then at least you can look at yourself in the mirror in the morning and say that you gave it your best shot.
I believe that to make the move from introvert to ambivert you need to show your hand with these opportunities. You have to stop being passive which I believe you are now. You need to be a tad more aggressive. You don't need to be a lion attacking prey aggressive but do you need to go for it.
If you see an opportunity go for it. Even if you don't know if it will work out, keep persisting and it may become the best decision you have even made.
Good luck, tell me how it goes.