Is it bad for me to use password special characters?

Before using password special characters, you should know that entropy is not a property of passwords. It is a property of password generation methods (or more generally, a property of probability distributions). Specifically, it is the expected number of bits of information that an attacker would need in order to identify the specific password that was generated, assuming they know the method that was used. If all possible passwords that you might generate have the same probability, this simplifies to an entropy of log2(number of possible passwords). So if your method is to select à, you have an entropy of 0; no additional information is needed to identify which of the single possible passwords was selected.

If your password is a sequence of somewhere between 1 and 16 às, you have an entropy of 4, since there are 16 possibilities and log2(16) = 4. If your password is three numbers between 0 and 15 inclusive, selected uniformly and independently, your entropy is 12, since there are 163 possibilities and log2(163) = log2(16)*3 = 12. But the password 15 3 7 doesn't have an entropy, because it's not a probability distribution; it's an item that was selected from one. Tools that claim to give you the entropy of a password are actually guessing as to what method you likely used to generate that password (and almost certainly guessing wrong), and giving you the entropy of the method they think you used. They report a high entropy for passwords with special characters because they believe the password was selected using a method that might have generated any special character in any position. If this assumption is false (which it is), then the entropy they report is nonsense. Using special characters in passwords is neither good nor bad. It doesn't matter which characters might end up in your password. It matters how many possibilities there are.