I work as a pharmacy tech and on Friday I messed up a transaction. This lady came in and picked up 2 medications and some other stuff like lotion. So I ring up her medication and lotion bottle and the total is like 46 dollars. One of the medication requires me to put in her ID in the computer (I think it's a controlled substance?) and I go on the computer in the back and put in her ID. While I'm doing that she swipes her card at the front register I checked her out in and I come back to the front and give her the medication and ID and I say "Have a good day!" Then I look on the register and see that she only paid 40 out of the 46 dollars and it still required 6 more dollars. She was already gone by the time I noticed this and I didn't know what to do so I started panicking. The customer line kept getting long and longer and I was freaking out because she didn't pay all of it and the register wouldn't let me do anything until the remaining money was paid. The pharmacy manager was doing inventory in the back and I didn't want to bother him because I bother him too much and he's going to think I'm stupid for letting her go before she paid and I didn't want that. I did the dumbest thing ever and decided to void the entire transaction. At the time I thought I only voided 6 dollars out of the 46 but I later realized "Oh **** no I voided the WHOLE thing so she never paid for ANY of it including the medication!" I thought screw the lotion bottle, the medication was more important. Because she never paid for it, it shows up as "unsold" in the system even though she has it, and next time she wants a refill or something she won't get one because the computer says the medication was never picked up. Then things get worse because I remembered one of them was a controlled substance and it's going to be missing from the inventory or something because I voided it out at the register so it will say she has one in the waiting bin but there is nothing there because she picked it up. I don't know what to do I feel so stupid. I don't want to get the pharmacist fired because of missing narcotics and I don't want to get fired either. What do I do? I tried not looking stupid and did something horrible. I'm so dumb. Help.