Charging a fee to join a tournament on a PC game and giving prizes

Q: I host tournaments on a game called Fortnite. People pay me a fee. Everyone to take part in these tournaments, and I pick a few of them every weekend to take part in the tournament. I give the top 3 prizes and sometimes cash rewards, prizes like perfumes, clothes etc. 

Is this what I am doing halaal earned money, I make profit of this too.

"Price adjustment" when shopping online

Q: When shopping online (Temu etc.), certain companies have something called "price adjustment". It is a benefit which gives the buyer back the difference in his previous purchase compared to the current price which is received by the buyer as credit in his account. 

For example, I purchased an item for R70. One week later it is R50 on the same online store. Using price adjustment one can claim back R20 as credit only to be used on that online store. Is it permissible to take that credit?

Haidh commencing while in Ihraam

Q: I am currently in Makkah to perform Umrah. 

Entered Ihram state 2 days ago. I was supposed to do my Tawaf and Sa'i yesterday. Unfortunately, I got my menses (1 week earlier than normal). I am still in my ihram state. 

I am due to leave Makkah in 3 days and my menses will not be finished by then. Thus I will not be able to perform Tawaf and complete my Umrah. I do no know when I can come back to perform Umrah again. 

I thus do not know if I should pay for Dam/sacrifice and exit my Ihram and if this is the right thing to do. 

Can you please help? 

Saying something through which a yameen and nazar takes place

Q: If a person says something like: 

“Wallāhi, I promise to Allah I won’t go on Instagram. If I do, I’ll give R50 in sadaqah as the expiation for me going onto Instagram.” 

1. Does this wording constitute a yamīn (oath), a nadhr (vow), or something else according to the Hanafi madhhab? 

2. Is there any way to cancel or revoke it before breaking it? 

3. If the person were to go on Instagram, would the prescribed kaffārah for a broken oath become obligatory, or would the R50 sadaqah suffice as the expiation?