chore: fix some typos in comment

diff --git a/src/psbt_io.h b/src/psbt_io.h
index 61c8be7..321ed56 100644
--- a/src/psbt_io.h
+++ b/src/psbt_io.h
@@ -195,7 +195,7 @@
 /* Input PSBT/PSET fields that must *not* be present in v2 */
 #define PSBT_IN_DISALLOWED_V2 ((uint64_t)0)
 
-/* Input PSET fields that are trivially mergable, i.e. can be
+/* Input PSET fields that are trivially mergeable, i.e. can be
  * copied when merging if missing the the destination input. */
 #define PSET_IN_MERGEABLE (PSET_FT(PSET_IN_ISSUANCE_VALUE_RANGEPROOF) | \
                            PSET_FT(PSET_IN_ISSUANCE_INFLATION_KEYS_RANGEPROOF) | \
diff --git a/src/sign.c b/src/sign.c
index f4a35a5..e94547a 100644
--- a/src/sign.c
+++ b/src/sign.c
@@ -388,7 +388,7 @@ int wally_ec_sig_from_bytes_aux(const unsigned char *priv_key, size_t priv_key_l
 
                 return WALLY_OK;
             }
-            /* Incremement nonce to grind for low-R */
+            /* Increment nonce to grind for low-R */
             entropy_p = extra_entropy;
             ++counter;
             uint32_to_le_bytes(counter, entropy_p);
diff --git a/src/test/test_anti_exfil.py b/src/test/test_anti_exfil.py
index 36bbeca..bfc3dee 100755
--- a/src/test/test_anti_exfil.py
+++ b/src/test/test_anti_exfil.py
@@ -73,7 +73,7 @@ class AntiExfilTests(unittest.TestCase):
         for args in [
             (None,    32, msg,     32, entropy, 32, signer_commitment, 33, flags, sig,     64), # Missing pubkey
             (pub_key, 31, msg,     32, entropy, 32, signer_commitment, 33, flags, sig,     64), # Incorrect pubkey length
-            (inv_pub, 32, msg,     32, entropy, 32, signer_commitment, 33, flags, sig,     64), # Invalud pubkey
+            (inv_pub, 32, msg,     32, entropy, 32, signer_commitment, 33, flags, sig,     64), # Invalid pubkey
             (pub_key, 32, None,    32, entropy, 32, signer_commitment, 33, flags, sig,     64), # Missing message
             (pub_key, 32, msg,     31, entropy, 32, signer_commitment, 33, flags, sig,     64), # Incorrect message length
             (pub_key, 32, inv_msg, 32, entropy, 32, signer_commitment, 33, flags, sig,     64), # Invalid message
diff --git a/src/test/test_sign.py b/src/test/test_sign.py
index bdd6392..6319935 100755
--- a/src/test/test_sign.py
+++ b/src/test/test_sign.py
@@ -279,7 +279,7 @@ class SignTests(unittest.TestCase):
 
         for args in [
             (None, 32, out1, 65, pub_key, 33),      # Missing message
-            (msg, 31, out1, 65, pub_key, 33),       # Incorrect messsage length
+            (msg, 31, out1, 65, pub_key, 33),       # Incorrect message length
             (msg, 32, None, 65, pub_key, 33),       # Missing signature
             (msg, 32, out1, 64, pub_key, 33),       # Incorrect signature length
             (msg, 32, out1, 65, None, 33),          # Missing pubkey
diff --git a/src/tx_io.c b/src/tx_io.c
index fb170a0..edf19e1 100644
--- a/src/tx_io.c
+++ b/src/tx_io.c
@@ -775,7 +775,7 @@ static void txio_bip341_init(cursor_io *io,
         const struct wally_map_item *item = NULL;
         item = wally_map_get_integer(io->cache, TXIO_SHA_TAPSIGHASH_CTX);
         if (item) {
-            /* Note we cached the intial sha256_ctx itself here and so memcpy it */
+            /* Note we cached the initial sha256_ctx itself here and so memcpy it */
             memcpy(&io->ctx, item->value, item->value_len);
             return;
         }