Can I use 2 more reactions at once?
Yes. Priority doesn't leave you until you choose to pass it, so you can play as many Reactions as you can afford in a row (Rule 312; FAQ #4744).
A few notes:
- You pay each cost as the card is put on the chain, not as it resolves.
- Everything resolves last-in-first-out (your second Reaction resolves before your first, then the original spell/ability).
- After each one resolves, priority is offered again — so your opponent gets chances to respond in between resolutions.
- This only works for cards/abilities that are legally timed in a Closed State (i.e., they have Reaction). Regular Actions need an Open State with an empty chain.